//===--- SemaDeclObjC.cpp - Semantic Analysis for ObjC Declarations -------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements semantic analysis for Objective C declarations. // //===----------------------------------------------------------------------===// #include "clang/Sema/SemaInternal.h" #include "clang/AST/ASTConsumer.h" #include "clang/AST/ASTContext.h" #include "clang/AST/ASTMutationListener.h" #include "clang/AST/RecursiveASTVisitor.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/Expr.h" #include "clang/AST/ExprObjC.h" #include "clang/Basic/SourceManager.h" #include "clang/Sema/DeclSpec.h" #include "clang/Sema/Lookup.h" #include "clang/Sema/Scope.h" #include "clang/Sema/ScopeInfo.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/DenseSet.h" #include "TypeLocBuilder.h" using namespace clang; /// Check whether the given method, which must be in the 'init' /// family, is a valid member of that family. /// /// \param receiverTypeIfCall - if null, check this as if declaring it; /// if non-null, check this as if making a call to it with the given /// receiver type /// /// \return true to indicate that there was an error and appropriate /// actions were taken bool Sema::checkInitMethod(ObjCMethodDecl *method, QualType receiverTypeIfCall) { if (method->isInvalidDecl()) return true; // This castAs is safe: methods that don't return an object // pointer won't be inferred as inits and will reject an explicit // objc_method_family(init). // We ignore protocols here. Should we? What about Class? const ObjCObjectType *result = method->getReturnType()->castAs()->getObjectType(); if (result->isObjCId()) { return false; } else if (result->isObjCClass()) { // fall through: always an error } else { ObjCInterfaceDecl *resultClass = result->getInterface(); assert(resultClass && "unexpected object type!"); // It's okay for the result type to still be a forward declaration // if we're checking an interface declaration. if (!resultClass->hasDefinition()) { if (receiverTypeIfCall.isNull() && !isa(method->getDeclContext())) return false; // Otherwise, we try to compare class types. } else { // If this method was declared in a protocol, we can't check // anything unless we have a receiver type that's an interface. const ObjCInterfaceDecl *receiverClass = nullptr; if (isa(method->getDeclContext())) { if (receiverTypeIfCall.isNull()) return false; receiverClass = receiverTypeIfCall->castAs() ->getInterfaceDecl(); // This can be null for calls to e.g. id. if (!receiverClass) return false; } else { receiverClass = method->getClassInterface(); assert(receiverClass && "method not associated with a class!"); } // If either class is a subclass of the other, it's fine. if (receiverClass->isSuperClassOf(resultClass) || resultClass->isSuperClassOf(receiverClass)) return false; } } SourceLocation loc = method->getLocation(); // If we're in a system header, and this is not a call, just make // the method unusable. if (receiverTypeIfCall.isNull() && getSourceManager().isInSystemHeader(loc)) { method->addAttr(UnavailableAttr::CreateImplicit(Context, "", UnavailableAttr::IR_ARCInitReturnsUnrelated, loc)); return true; } // Otherwise, it's an error. Diag(loc, diag::err_arc_init_method_unrelated_result_type); method->setInvalidDecl(); return true; } void Sema::CheckObjCMethodOverride(ObjCMethodDecl *NewMethod, const ObjCMethodDecl *Overridden) { if (Overridden->hasRelatedResultType() && !NewMethod->hasRelatedResultType()) { // This can only happen when the method follows a naming convention that // implies a related result type, and the original (overridden) method has // a suitable return type, but the new (overriding) method does not have // a suitable return type. QualType ResultType = NewMethod->getReturnType(); SourceRange ResultTypeRange = NewMethod->getReturnTypeSourceRange(); // Figure out which class this method is part of, if any. ObjCInterfaceDecl *CurrentClass = dyn_cast(NewMethod->getDeclContext()); if (!CurrentClass) { DeclContext *DC = NewMethod->getDeclContext(); if (ObjCCategoryDecl *Cat = dyn_cast(DC)) CurrentClass = Cat->getClassInterface(); else if (ObjCImplDecl *Impl = dyn_cast(DC)) CurrentClass = Impl->getClassInterface(); else if (ObjCCategoryImplDecl *CatImpl = dyn_cast(DC)) CurrentClass = CatImpl->getClassInterface(); } if (CurrentClass) { Diag(NewMethod->getLocation(), diag::warn_related_result_type_compatibility_class) << Context.getObjCInterfaceType(CurrentClass) << ResultType << ResultTypeRange; } else { Diag(NewMethod->getLocation(), diag::warn_related_result_type_compatibility_protocol) << ResultType << ResultTypeRange; } if (ObjCMethodFamily Family = Overridden->getMethodFamily()) Diag(Overridden->getLocation(), diag::note_related_result_type_family) << /*overridden method*/ 0 << Family; else Diag(Overridden->getLocation(), diag::note_related_result_type_overridden); } if (getLangOpts().ObjCAutoRefCount) { if ((NewMethod->hasAttr() != Overridden->hasAttr())) { Diag(NewMethod->getLocation(), diag::err_nsreturns_retained_attribute_mismatch) << 1; Diag(Overridden->getLocation(), diag::note_previous_decl) << "method"; } if ((NewMethod->hasAttr() != Overridden->hasAttr())) { Diag(NewMethod->getLocation(), diag::err_nsreturns_retained_attribute_mismatch) << 0; Diag(Overridden->getLocation(), diag::note_previous_decl) << "method"; } ObjCMethodDecl::param_const_iterator oi = Overridden->param_begin(), oe = Overridden->param_end(); for (ObjCMethodDecl::param_iterator ni = NewMethod->param_begin(), ne = NewMethod->param_end(); ni != ne && oi != oe; ++ni, ++oi) { const ParmVarDecl *oldDecl = (*oi); ParmVarDecl *newDecl = (*ni); if (newDecl->hasAttr() != oldDecl->hasAttr()) { Diag(newDecl->getLocation(), diag::err_nsconsumed_attribute_mismatch); Diag(oldDecl->getLocation(), diag::note_previous_decl) << "parameter"; } } } } /// \brief Check a method declaration for compatibility with the Objective-C /// ARC conventions. bool Sema::CheckARCMethodDecl(ObjCMethodDecl *method) { ObjCMethodFamily family = method->getMethodFamily(); switch (family) { case OMF_None: case OMF_finalize: case OMF_retain: case OMF_release: case OMF_autorelease: case OMF_retainCount: case OMF_self: case OMF_initialize: case OMF_performSelector: return false; case OMF_dealloc: if (!Context.hasSameType(method->getReturnType(), Context.VoidTy)) { SourceRange ResultTypeRange = method->getReturnTypeSourceRange(); if (ResultTypeRange.isInvalid()) Diag(method->getLocation(), diag::error_dealloc_bad_result_type) << method->getReturnType() << FixItHint::CreateInsertion(method->getSelectorLoc(0), "(void)"); else Diag(method->getLocation(), diag::error_dealloc_bad_result_type) << method->getReturnType() << FixItHint::CreateReplacement(ResultTypeRange, "void"); return true; } return false; case OMF_init: // If the method doesn't obey the init rules, don't bother annotating it. if (checkInitMethod(method, QualType())) return true; method->addAttr(NSConsumesSelfAttr::CreateImplicit(Context)); // Don't add a second copy of this attribute, but otherwise don't // let it be suppressed. if (method->hasAttr()) return false; break; case OMF_alloc: case OMF_copy: case OMF_mutableCopy: case OMF_new: if (method->hasAttr() || method->hasAttr() || method->hasAttr()) return false; break; } method->addAttr(NSReturnsRetainedAttr::CreateImplicit(Context)); return false; } static void DiagnoseObjCImplementedDeprecations(Sema &S, NamedDecl *ND, SourceLocation ImplLoc, int select) { if (ND && ND->isDeprecated()) { S.Diag(ImplLoc, diag::warn_deprecated_def) << select; if (select == 0) S.Diag(ND->getLocation(), diag::note_method_declared_at) << ND->getDeclName(); else S.Diag(ND->getLocation(), diag::note_previous_decl) << "class"; } } /// AddAnyMethodToGlobalPool - Add any method, instance or factory to global /// pool. void Sema::AddAnyMethodToGlobalPool(Decl *D) { ObjCMethodDecl *MDecl = dyn_cast_or_null(D); // If we don't have a valid method decl, simply return. if (!MDecl) return; if (MDecl->isInstanceMethod()) AddInstanceMethodToGlobalPool(MDecl, true); else AddFactoryMethodToGlobalPool(MDecl, true); } /// HasExplicitOwnershipAttr - returns true when pointer to ObjC pointer /// has explicit ownership attribute; false otherwise. static bool HasExplicitOwnershipAttr(Sema &S, ParmVarDecl *Param) { QualType T = Param->getType(); if (const PointerType *PT = T->getAs()) { T = PT->getPointeeType(); } else if (const ReferenceType *RT = T->getAs()) { T = RT->getPointeeType(); } else { return true; } // If we have a lifetime qualifier, but it's local, we must have // inferred it. So, it is implicit. return !T.getLocalQualifiers().hasObjCLifetime(); } /// ActOnStartOfObjCMethodDef - This routine sets up parameters; invisible /// and user declared, in the method definition's AST. void Sema::ActOnStartOfObjCMethodDef(Scope *FnBodyScope, Decl *D) { assert((getCurMethodDecl() == nullptr) && "Methodparsing confused"); ObjCMethodDecl *MDecl = dyn_cast_or_null(D); // If we don't have a valid method decl, simply return. if (!MDecl) return; // Allow all of Sema to see that we are entering a method definition. PushDeclContext(FnBodyScope, MDecl); PushFunctionScope(); // Create Decl objects for each parameter, entrring them in the scope for // binding to their use. // Insert the invisible arguments, self and _cmd! MDecl->createImplicitParams(Context, MDecl->getClassInterface()); PushOnScopeChains(MDecl->getSelfDecl(), FnBodyScope); PushOnScopeChains(MDecl->getCmdDecl(), FnBodyScope); // The ObjC parser requires parameter names so there's no need to check. CheckParmsForFunctionDef(MDecl->parameters(), /*CheckParameterNames=*/false); // Introduce all of the other parameters into this scope. for (auto *Param : MDecl->parameters()) { if (!Param->isInvalidDecl() && getLangOpts().ObjCAutoRefCount && !HasExplicitOwnershipAttr(*this, Param)) Diag(Param->getLocation(), diag::warn_arc_strong_pointer_objc_pointer) << Param->getType(); if (Param->getIdentifier()) PushOnScopeChains(Param, FnBodyScope); } // In ARC, disallow definition of retain/release/autorelease/retainCount if (getLangOpts().ObjCAutoRefCount) { switch (MDecl->getMethodFamily()) { case OMF_retain: case OMF_retainCount: case OMF_release: case OMF_autorelease: Diag(MDecl->getLocation(), diag::err_arc_illegal_method_def) << 0 << MDecl->getSelector(); break; case OMF_None: case OMF_dealloc: case OMF_finalize: case OMF_alloc: case OMF_init: case OMF_mutableCopy: case OMF_copy: case OMF_new: case OMF_self: case OMF_initialize: case OMF_performSelector: break; } } // Warn on deprecated methods under -Wdeprecated-implementations, // and prepare for warning on missing super calls. if (ObjCInterfaceDecl *IC = MDecl->getClassInterface()) { ObjCMethodDecl *IMD = IC->lookupMethod(MDecl->getSelector(), MDecl->isInstanceMethod()); if (IMD) { ObjCImplDecl *ImplDeclOfMethodDef = dyn_cast(MDecl->getDeclContext()); ObjCContainerDecl *ContDeclOfMethodDecl = dyn_cast(IMD->getDeclContext()); ObjCImplDecl *ImplDeclOfMethodDecl = nullptr; if (ObjCInterfaceDecl *OID = dyn_cast(ContDeclOfMethodDecl)) ImplDeclOfMethodDecl = OID->getImplementation(); else if (ObjCCategoryDecl *CD = dyn_cast(ContDeclOfMethodDecl)) { if (CD->IsClassExtension()) { if (ObjCInterfaceDecl *OID = CD->getClassInterface()) ImplDeclOfMethodDecl = OID->getImplementation(); } else ImplDeclOfMethodDecl = CD->getImplementation(); } // No need to issue deprecated warning if deprecated mehod in class/category // is being implemented in its own implementation (no overriding is involved). if (!ImplDeclOfMethodDecl || ImplDeclOfMethodDecl != ImplDeclOfMethodDef) DiagnoseObjCImplementedDeprecations(*this, dyn_cast(IMD), MDecl->getLocation(), 0); } if (MDecl->getMethodFamily() == OMF_init) { if (MDecl->isDesignatedInitializerForTheInterface()) { getCurFunction()->ObjCIsDesignatedInit = true; getCurFunction()->ObjCWarnForNoDesignatedInitChain = IC->getSuperClass() != nullptr; } else if (IC->hasDesignatedInitializers()) { getCurFunction()->ObjCIsSecondaryInit = true; getCurFunction()->ObjCWarnForNoInitDelegation = true; } } // If this is "dealloc" or "finalize", set some bit here. // Then in ActOnSuperMessage() (SemaExprObjC), set it back to false. // Finally, in ActOnFinishFunctionBody() (SemaDecl), warn if flag is set. // Only do this if the current class actually has a superclass. if (const ObjCInterfaceDecl *SuperClass = IC->getSuperClass()) { ObjCMethodFamily Family = MDecl->getMethodFamily(); if (Family == OMF_dealloc) { if (!(getLangOpts().ObjCAutoRefCount || getLangOpts().getGC() == LangOptions::GCOnly)) getCurFunction()->ObjCShouldCallSuper = true; } else if (Family == OMF_finalize) { if (Context.getLangOpts().getGC() != LangOptions::NonGC) getCurFunction()->ObjCShouldCallSuper = true; } else { const ObjCMethodDecl *SuperMethod = SuperClass->lookupMethod(MDecl->getSelector(), MDecl->isInstanceMethod()); getCurFunction()->ObjCShouldCallSuper = (SuperMethod && SuperMethod->hasAttr()); } } } } namespace { // Callback to only accept typo corrections that are Objective-C classes. // If an ObjCInterfaceDecl* is given to the constructor, then the validation // function will reject corrections to that class. class ObjCInterfaceValidatorCCC : public CorrectionCandidateCallback { public: ObjCInterfaceValidatorCCC() : CurrentIDecl(nullptr) {} explicit ObjCInterfaceValidatorCCC(ObjCInterfaceDecl *IDecl) : CurrentIDecl(IDecl) {} bool ValidateCandidate(const TypoCorrection &candidate) override { ObjCInterfaceDecl *ID = candidate.getCorrectionDeclAs(); return ID && !declaresSameEntity(ID, CurrentIDecl); } private: ObjCInterfaceDecl *CurrentIDecl; }; } // end anonymous namespace static void diagnoseUseOfProtocols(Sema &TheSema, ObjCContainerDecl *CD, ObjCProtocolDecl *const *ProtoRefs, unsigned NumProtoRefs, const SourceLocation *ProtoLocs) { assert(ProtoRefs); // Diagnose availability in the context of the ObjC container. Sema::ContextRAII SavedContext(TheSema, CD); for (unsigned i = 0; i < NumProtoRefs; ++i) { (void)TheSema.DiagnoseUseOfDecl(ProtoRefs[i], ProtoLocs[i]); } } void Sema:: ActOnSuperClassOfClassInterface(Scope *S, SourceLocation AtInterfaceLoc, ObjCInterfaceDecl *IDecl, IdentifierInfo *ClassName, SourceLocation ClassLoc, IdentifierInfo *SuperName, SourceLocation SuperLoc, ArrayRef SuperTypeArgs, SourceRange SuperTypeArgsRange) { // Check if a different kind of symbol declared in this scope. NamedDecl *PrevDecl = LookupSingleName(TUScope, SuperName, SuperLoc, LookupOrdinaryName); if (!PrevDecl) { // Try to correct for a typo in the superclass name without correcting // to the class we're defining. if (TypoCorrection Corrected = CorrectTypo( DeclarationNameInfo(SuperName, SuperLoc), LookupOrdinaryName, TUScope, nullptr, llvm::make_unique(IDecl), CTK_ErrorRecovery)) { diagnoseTypo(Corrected, PDiag(diag::err_undef_superclass_suggest) << SuperName << ClassName); PrevDecl = Corrected.getCorrectionDeclAs(); } } if (declaresSameEntity(PrevDecl, IDecl)) { Diag(SuperLoc, diag::err_recursive_superclass) << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc); IDecl->setEndOfDefinitionLoc(ClassLoc); } else { ObjCInterfaceDecl *SuperClassDecl = dyn_cast_or_null(PrevDecl); QualType SuperClassType; // Diagnose classes that inherit from deprecated classes. if (SuperClassDecl) { (void)DiagnoseUseOfDecl(SuperClassDecl, SuperLoc); SuperClassType = Context.getObjCInterfaceType(SuperClassDecl); } if (PrevDecl && !SuperClassDecl) { // The previous declaration was not a class decl. Check if we have a // typedef. If we do, get the underlying class type. if (const TypedefNameDecl *TDecl = dyn_cast_or_null(PrevDecl)) { QualType T = TDecl->getUnderlyingType(); if (T->isObjCObjectType()) { if (NamedDecl *IDecl = T->getAs()->getInterface()) { SuperClassDecl = dyn_cast(IDecl); SuperClassType = Context.getTypeDeclType(TDecl); // This handles the following case: // @interface NewI @end // typedef NewI DeprI __attribute__((deprecated("blah"))) // @interface SI : DeprI /* warn here */ @end (void)DiagnoseUseOfDecl(const_cast(TDecl), SuperLoc); } } } // This handles the following case: // // typedef int SuperClass; // @interface MyClass : SuperClass {} @end // if (!SuperClassDecl) { Diag(SuperLoc, diag::err_redefinition_different_kind) << SuperName; Diag(PrevDecl->getLocation(), diag::note_previous_definition); } } if (!dyn_cast_or_null(PrevDecl)) { if (!SuperClassDecl) Diag(SuperLoc, diag::err_undef_superclass) << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc); else if (RequireCompleteType(SuperLoc, SuperClassType, diag::err_forward_superclass, SuperClassDecl->getDeclName(), ClassName, SourceRange(AtInterfaceLoc, ClassLoc))) { SuperClassDecl = nullptr; SuperClassType = QualType(); } } if (SuperClassType.isNull()) { assert(!SuperClassDecl && "Failed to set SuperClassType?"); return; } // Handle type arguments on the superclass. TypeSourceInfo *SuperClassTInfo = nullptr; if (!SuperTypeArgs.empty()) { TypeResult fullSuperClassType = actOnObjCTypeArgsAndProtocolQualifiers( S, SuperLoc, CreateParsedType(SuperClassType, nullptr), SuperTypeArgsRange.getBegin(), SuperTypeArgs, SuperTypeArgsRange.getEnd(), SourceLocation(), { }, { }, SourceLocation()); if (!fullSuperClassType.isUsable()) return; SuperClassType = GetTypeFromParser(fullSuperClassType.get(), &SuperClassTInfo); } if (!SuperClassTInfo) { SuperClassTInfo = Context.getTrivialTypeSourceInfo(SuperClassType, SuperLoc); } IDecl->setSuperClass(SuperClassTInfo); IDecl->setEndOfDefinitionLoc(SuperClassTInfo->getTypeLoc().getLocEnd()); } } DeclResult Sema::actOnObjCTypeParam(Scope *S, ObjCTypeParamVariance variance, SourceLocation varianceLoc, unsigned index, IdentifierInfo *paramName, SourceLocation paramLoc, SourceLocation colonLoc, ParsedType parsedTypeBound) { // If there was an explicitly-provided type bound, check it. TypeSourceInfo *typeBoundInfo = nullptr; if (parsedTypeBound) { // The type bound can be any Objective-C pointer type. QualType typeBound = GetTypeFromParser(parsedTypeBound, &typeBoundInfo); if (typeBound->isObjCObjectPointerType()) { // okay } else if (typeBound->isObjCObjectType()) { // The user forgot the * on an Objective-C pointer type, e.g., // "T : NSView". SourceLocation starLoc = getLocForEndOfToken( typeBoundInfo->getTypeLoc().getEndLoc()); Diag(typeBoundInfo->getTypeLoc().getBeginLoc(), diag::err_objc_type_param_bound_missing_pointer) << typeBound << paramName << FixItHint::CreateInsertion(starLoc, " *"); // Create a new type location builder so we can update the type // location information we have. TypeLocBuilder builder; builder.pushFullCopy(typeBoundInfo->getTypeLoc()); // Create the Objective-C pointer type. typeBound = Context.getObjCObjectPointerType(typeBound); ObjCObjectPointerTypeLoc newT = builder.push(typeBound); newT.setStarLoc(starLoc); // Form the new type source information. typeBoundInfo = builder.getTypeSourceInfo(Context, typeBound); } else { // Not a valid type bound. Diag(typeBoundInfo->getTypeLoc().getBeginLoc(), diag::err_objc_type_param_bound_nonobject) << typeBound << paramName; // Forget the bound; we'll default to id later. typeBoundInfo = nullptr; } // Type bounds cannot have qualifiers (even indirectly) or explicit // nullability. if (typeBoundInfo) { QualType typeBound = typeBoundInfo->getType(); TypeLoc qual = typeBoundInfo->getTypeLoc().findExplicitQualifierLoc(); if (qual || typeBound.hasQualifiers()) { bool diagnosed = false; SourceRange rangeToRemove; if (qual) { if (auto attr = qual.getAs()) { rangeToRemove = attr.getLocalSourceRange(); if (attr.getTypePtr()->getImmediateNullability()) { Diag(attr.getLocStart(), diag::err_objc_type_param_bound_explicit_nullability) << paramName << typeBound << FixItHint::CreateRemoval(rangeToRemove); diagnosed = true; } } } if (!diagnosed) { Diag(qual ? qual.getLocStart() : typeBoundInfo->getTypeLoc().getLocStart(), diag::err_objc_type_param_bound_qualified) << paramName << typeBound << typeBound.getQualifiers().getAsString() << FixItHint::CreateRemoval(rangeToRemove); } // If the type bound has qualifiers other than CVR, we need to strip // them or we'll probably assert later when trying to apply new // qualifiers. Qualifiers quals = typeBound.getQualifiers(); quals.removeCVRQualifiers(); if (!quals.empty()) { typeBoundInfo = Context.getTrivialTypeSourceInfo(typeBound.getUnqualifiedType()); } } } } // If there was no explicit type bound (or we removed it due to an error), // use 'id' instead. if (!typeBoundInfo) { colonLoc = SourceLocation(); typeBoundInfo = Context.getTrivialTypeSourceInfo(Context.getObjCIdType()); } // Create the type parameter. return ObjCTypeParamDecl::Create(Context, CurContext, variance, varianceLoc, index, paramLoc, paramName, colonLoc, typeBoundInfo); } ObjCTypeParamList *Sema::actOnObjCTypeParamList(Scope *S, SourceLocation lAngleLoc, ArrayRef typeParamsIn, SourceLocation rAngleLoc) { // We know that the array only contains Objective-C type parameters. ArrayRef typeParams( reinterpret_cast(typeParamsIn.data()), typeParamsIn.size()); // Diagnose redeclarations of type parameters. // We do this now because Objective-C type parameters aren't pushed into // scope until later (after the instance variable block), but we want the // diagnostics to occur right after we parse the type parameter list. llvm::SmallDenseMap knownParams; for (auto typeParam : typeParams) { auto known = knownParams.find(typeParam->getIdentifier()); if (known != knownParams.end()) { Diag(typeParam->getLocation(), diag::err_objc_type_param_redecl) << typeParam->getIdentifier() << SourceRange(known->second->getLocation()); typeParam->setInvalidDecl(); } else { knownParams.insert(std::make_pair(typeParam->getIdentifier(), typeParam)); // Push the type parameter into scope. PushOnScopeChains(typeParam, S, /*AddToContext=*/false); } } // Create the parameter list. return ObjCTypeParamList::create(Context, lAngleLoc, typeParams, rAngleLoc); } void Sema::popObjCTypeParamList(Scope *S, ObjCTypeParamList *typeParamList) { for (auto typeParam : *typeParamList) { if (!typeParam->isInvalidDecl()) { S->RemoveDecl(typeParam); IdResolver.RemoveDecl(typeParam); } } } namespace { /// The context in which an Objective-C type parameter list occurs, for use /// in diagnostics. enum class TypeParamListContext { ForwardDeclaration, Definition, Category, Extension }; } // end anonymous namespace /// Check consistency between two Objective-C type parameter lists, e.g., /// between a category/extension and an \@interface or between an \@class and an /// \@interface. static bool checkTypeParamListConsistency(Sema &S, ObjCTypeParamList *prevTypeParams, ObjCTypeParamList *newTypeParams, TypeParamListContext newContext) { // If the sizes don't match, complain about that. if (prevTypeParams->size() != newTypeParams->size()) { SourceLocation diagLoc; if (newTypeParams->size() > prevTypeParams->size()) { diagLoc = newTypeParams->begin()[prevTypeParams->size()]->getLocation(); } else { diagLoc = S.getLocForEndOfToken(newTypeParams->back()->getLocEnd()); } S.Diag(diagLoc, diag::err_objc_type_param_arity_mismatch) << static_cast(newContext) << (newTypeParams->size() > prevTypeParams->size()) << prevTypeParams->size() << newTypeParams->size(); return true; } // Match up the type parameters. for (unsigned i = 0, n = prevTypeParams->size(); i != n; ++i) { ObjCTypeParamDecl *prevTypeParam = prevTypeParams->begin()[i]; ObjCTypeParamDecl *newTypeParam = newTypeParams->begin()[i]; // Check for consistency of the variance. if (newTypeParam->getVariance() != prevTypeParam->getVariance()) { if (newTypeParam->getVariance() == ObjCTypeParamVariance::Invariant && newContext != TypeParamListContext::Definition) { // When the new type parameter is invariant and is not part // of the definition, just propagate the variance. newTypeParam->setVariance(prevTypeParam->getVariance()); } else if (prevTypeParam->getVariance() == ObjCTypeParamVariance::Invariant && !(isa(prevTypeParam->getDeclContext()) && cast(prevTypeParam->getDeclContext()) ->getDefinition() == prevTypeParam->getDeclContext())) { // When the old parameter is invariant and was not part of the // definition, just ignore the difference because it doesn't // matter. } else { { // Diagnose the conflict and update the second declaration. SourceLocation diagLoc = newTypeParam->getVarianceLoc(); if (diagLoc.isInvalid()) diagLoc = newTypeParam->getLocStart(); auto diag = S.Diag(diagLoc, diag::err_objc_type_param_variance_conflict) << static_cast(newTypeParam->getVariance()) << newTypeParam->getDeclName() << static_cast(prevTypeParam->getVariance()) << prevTypeParam->getDeclName(); switch (prevTypeParam->getVariance()) { case ObjCTypeParamVariance::Invariant: diag << FixItHint::CreateRemoval(newTypeParam->getVarianceLoc()); break; case ObjCTypeParamVariance::Covariant: case ObjCTypeParamVariance::Contravariant: { StringRef newVarianceStr = prevTypeParam->getVariance() == ObjCTypeParamVariance::Covariant ? "__covariant" : "__contravariant"; if (newTypeParam->getVariance() == ObjCTypeParamVariance::Invariant) { diag << FixItHint::CreateInsertion(newTypeParam->getLocStart(), (newVarianceStr + " ").str()); } else { diag << FixItHint::CreateReplacement(newTypeParam->getVarianceLoc(), newVarianceStr); } } } } S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here) << prevTypeParam->getDeclName(); // Override the variance. newTypeParam->setVariance(prevTypeParam->getVariance()); } } // If the bound types match, there's nothing to do. if (S.Context.hasSameType(prevTypeParam->getUnderlyingType(), newTypeParam->getUnderlyingType())) continue; // If the new type parameter's bound was explicit, complain about it being // different from the original. if (newTypeParam->hasExplicitBound()) { SourceRange newBoundRange = newTypeParam->getTypeSourceInfo() ->getTypeLoc().getSourceRange(); S.Diag(newBoundRange.getBegin(), diag::err_objc_type_param_bound_conflict) << newTypeParam->getUnderlyingType() << newTypeParam->getDeclName() << prevTypeParam->hasExplicitBound() << prevTypeParam->getUnderlyingType() << (newTypeParam->getDeclName() == prevTypeParam->getDeclName()) << prevTypeParam->getDeclName() << FixItHint::CreateReplacement( newBoundRange, prevTypeParam->getUnderlyingType().getAsString( S.Context.getPrintingPolicy())); S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here) << prevTypeParam->getDeclName(); // Override the new type parameter's bound type with the previous type, // so that it's consistent. newTypeParam->setTypeSourceInfo( S.Context.getTrivialTypeSourceInfo(prevTypeParam->getUnderlyingType())); continue; } // The new type parameter got the implicit bound of 'id'. That's okay for // categories and extensions (overwrite it later), but not for forward // declarations and @interfaces, because those must be standalone. if (newContext == TypeParamListContext::ForwardDeclaration || newContext == TypeParamListContext::Definition) { // Diagnose this problem for forward declarations and definitions. SourceLocation insertionLoc = S.getLocForEndOfToken(newTypeParam->getLocation()); std::string newCode = " : " + prevTypeParam->getUnderlyingType().getAsString( S.Context.getPrintingPolicy()); S.Diag(newTypeParam->getLocation(), diag::err_objc_type_param_bound_missing) << prevTypeParam->getUnderlyingType() << newTypeParam->getDeclName() << (newContext == TypeParamListContext::ForwardDeclaration) << FixItHint::CreateInsertion(insertionLoc, newCode); S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here) << prevTypeParam->getDeclName(); } // Update the new type parameter's bound to match the previous one. newTypeParam->setTypeSourceInfo( S.Context.getTrivialTypeSourceInfo(prevTypeParam->getUnderlyingType())); } return false; } Decl *Sema:: ActOnStartClassInterface(Scope *S, SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName, SourceLocation ClassLoc, ObjCTypeParamList *typeParamList, IdentifierInfo *SuperName, SourceLocation SuperLoc, ArrayRef SuperTypeArgs, SourceRange SuperTypeArgsRange, Decl * const *ProtoRefs, unsigned NumProtoRefs, const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc, AttributeList *AttrList) { assert(ClassName && "Missing class identifier"); // Check for another declaration kind with the same name. NamedDecl *PrevDecl = LookupSingleName(TUScope, ClassName, ClassLoc, LookupOrdinaryName, ForRedeclaration); if (PrevDecl && !isa(PrevDecl)) { Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName; Diag(PrevDecl->getLocation(), diag::note_previous_definition); } // Create a declaration to describe this @interface. ObjCInterfaceDecl* PrevIDecl = dyn_cast_or_null(PrevDecl); if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) { // A previous decl with a different name is because of // @compatibility_alias, for example: // \code // @class NewImage; // @compatibility_alias OldImage NewImage; // \endcode // A lookup for 'OldImage' will return the 'NewImage' decl. // // In such a case use the real declaration name, instead of the alias one, // otherwise we will break IdentifierResolver and redecls-chain invariants. // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl // has been aliased. ClassName = PrevIDecl->getIdentifier(); } // If there was a forward declaration with type parameters, check // for consistency. if (PrevIDecl) { if (ObjCTypeParamList *prevTypeParamList = PrevIDecl->getTypeParamList()) { if (typeParamList) { // Both have type parameter lists; check for consistency. if (checkTypeParamListConsistency(*this, prevTypeParamList, typeParamList, TypeParamListContext::Definition)) { typeParamList = nullptr; } } else { Diag(ClassLoc, diag::err_objc_parameterized_forward_class_first) << ClassName; Diag(prevTypeParamList->getLAngleLoc(), diag::note_previous_decl) << ClassName; // Clone the type parameter list. SmallVector clonedTypeParams; for (auto typeParam : *prevTypeParamList) { clonedTypeParams.push_back( ObjCTypeParamDecl::Create( Context, CurContext, typeParam->getVariance(), SourceLocation(), typeParam->getIndex(), SourceLocation(), typeParam->getIdentifier(), SourceLocation(), Context.getTrivialTypeSourceInfo(typeParam->getUnderlyingType()))); } typeParamList = ObjCTypeParamList::create(Context, SourceLocation(), clonedTypeParams, SourceLocation()); } } } ObjCInterfaceDecl *IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtInterfaceLoc, ClassName, typeParamList, PrevIDecl, ClassLoc); if (PrevIDecl) { // Class already seen. Was it a definition? if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) { Diag(AtInterfaceLoc, diag::err_duplicate_class_def) << PrevIDecl->getDeclName(); Diag(Def->getLocation(), diag::note_previous_definition); IDecl->setInvalidDecl(); } } if (AttrList) ProcessDeclAttributeList(TUScope, IDecl, AttrList); PushOnScopeChains(IDecl, TUScope); // Start the definition of this class. If we're in a redefinition case, there // may already be a definition, so we'll end up adding to it. if (!IDecl->hasDefinition()) IDecl->startDefinition(); if (SuperName) { // Diagnose availability in the context of the @interface. ContextRAII SavedContext(*this, IDecl); ActOnSuperClassOfClassInterface(S, AtInterfaceLoc, IDecl, ClassName, ClassLoc, SuperName, SuperLoc, SuperTypeArgs, SuperTypeArgsRange); } else { // we have a root class. IDecl->setEndOfDefinitionLoc(ClassLoc); } // Check then save referenced protocols. if (NumProtoRefs) { diagnoseUseOfProtocols(*this, IDecl, (ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs, ProtoLocs); IDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs, ProtoLocs, Context); IDecl->setEndOfDefinitionLoc(EndProtoLoc); } CheckObjCDeclScope(IDecl); return ActOnObjCContainerStartDefinition(IDecl); } /// ActOnTypedefedProtocols - this action finds protocol list as part of the /// typedef'ed use for a qualified super class and adds them to the list /// of the protocols. void Sema::ActOnTypedefedProtocols(SmallVectorImpl &ProtocolRefs, IdentifierInfo *SuperName, SourceLocation SuperLoc) { if (!SuperName) return; NamedDecl* IDecl = LookupSingleName(TUScope, SuperName, SuperLoc, LookupOrdinaryName); if (!IDecl) return; if (const TypedefNameDecl *TDecl = dyn_cast_or_null(IDecl)) { QualType T = TDecl->getUnderlyingType(); if (T->isObjCObjectType()) if (const ObjCObjectType *OPT = T->getAs()) ProtocolRefs.append(OPT->qual_begin(), OPT->qual_end()); } } /// ActOnCompatibilityAlias - this action is called after complete parsing of /// a \@compatibility_alias declaration. It sets up the alias relationships. Decl *Sema::ActOnCompatibilityAlias(SourceLocation AtLoc, IdentifierInfo *AliasName, SourceLocation AliasLocation, IdentifierInfo *ClassName, SourceLocation ClassLocation) { // Look for previous declaration of alias name NamedDecl *ADecl = LookupSingleName(TUScope, AliasName, AliasLocation, LookupOrdinaryName, ForRedeclaration); if (ADecl) { Diag(AliasLocation, diag::err_conflicting_aliasing_type) << AliasName; Diag(ADecl->getLocation(), diag::note_previous_declaration); return nullptr; } // Check for class declaration NamedDecl *CDeclU = LookupSingleName(TUScope, ClassName, ClassLocation, LookupOrdinaryName, ForRedeclaration); if (const TypedefNameDecl *TDecl = dyn_cast_or_null(CDeclU)) { QualType T = TDecl->getUnderlyingType(); if (T->isObjCObjectType()) { if (NamedDecl *IDecl = T->getAs()->getInterface()) { ClassName = IDecl->getIdentifier(); CDeclU = LookupSingleName(TUScope, ClassName, ClassLocation, LookupOrdinaryName, ForRedeclaration); } } } ObjCInterfaceDecl *CDecl = dyn_cast_or_null(CDeclU); if (!CDecl) { Diag(ClassLocation, diag::warn_undef_interface) << ClassName; if (CDeclU) Diag(CDeclU->getLocation(), diag::note_previous_declaration); return nullptr; } // Everything checked out, instantiate a new alias declaration AST. ObjCCompatibleAliasDecl *AliasDecl = ObjCCompatibleAliasDecl::Create(Context, CurContext, AtLoc, AliasName, CDecl); if (!CheckObjCDeclScope(AliasDecl)) PushOnScopeChains(AliasDecl, TUScope); return AliasDecl; } bool Sema::CheckForwardProtocolDeclarationForCircularDependency( IdentifierInfo *PName, SourceLocation &Ploc, SourceLocation PrevLoc, const ObjCList &PList) { bool res = false; for (ObjCList::iterator I = PList.begin(), E = PList.end(); I != E; ++I) { if (ObjCProtocolDecl *PDecl = LookupProtocol((*I)->getIdentifier(), Ploc)) { if (PDecl->getIdentifier() == PName) { Diag(Ploc, diag::err_protocol_has_circular_dependency); Diag(PrevLoc, diag::note_previous_definition); res = true; } if (!PDecl->hasDefinition()) continue; if (CheckForwardProtocolDeclarationForCircularDependency(PName, Ploc, PDecl->getLocation(), PDecl->getReferencedProtocols())) res = true; } } return res; } Decl * Sema::ActOnStartProtocolInterface(SourceLocation AtProtoInterfaceLoc, IdentifierInfo *ProtocolName, SourceLocation ProtocolLoc, Decl * const *ProtoRefs, unsigned NumProtoRefs, const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc, AttributeList *AttrList) { bool err = false; // FIXME: Deal with AttrList. assert(ProtocolName && "Missing protocol identifier"); ObjCProtocolDecl *PrevDecl = LookupProtocol(ProtocolName, ProtocolLoc, ForRedeclaration); ObjCProtocolDecl *PDecl = nullptr; if (ObjCProtocolDecl *Def = PrevDecl? PrevDecl->getDefinition() : nullptr) { // If we already have a definition, complain. Diag(ProtocolLoc, diag::warn_duplicate_protocol_def) << ProtocolName; Diag(Def->getLocation(), diag::note_previous_definition); // Create a new protocol that is completely distinct from previous // declarations, and do not make this protocol available for name lookup. // That way, we'll end up completely ignoring the duplicate. // FIXME: Can we turn this into an error? PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName, ProtocolLoc, AtProtoInterfaceLoc, /*PrevDecl=*/nullptr); PDecl->startDefinition(); } else { if (PrevDecl) { // Check for circular dependencies among protocol declarations. This can // only happen if this protocol was forward-declared. ObjCList PList; PList.set((ObjCProtocolDecl *const*)ProtoRefs, NumProtoRefs, Context); err = CheckForwardProtocolDeclarationForCircularDependency( ProtocolName, ProtocolLoc, PrevDecl->getLocation(), PList); } // Create the new declaration. PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName, ProtocolLoc, AtProtoInterfaceLoc, /*PrevDecl=*/PrevDecl); PushOnScopeChains(PDecl, TUScope); PDecl->startDefinition(); } if (AttrList) ProcessDeclAttributeList(TUScope, PDecl, AttrList); // Merge attributes from previous declarations. if (PrevDecl) mergeDeclAttributes(PDecl, PrevDecl); if (!err && NumProtoRefs ) { /// Check then save referenced protocols. diagnoseUseOfProtocols(*this, PDecl, (ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs, ProtoLocs); PDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs, ProtoLocs, Context); } CheckObjCDeclScope(PDecl); return ActOnObjCContainerStartDefinition(PDecl); } static bool NestedProtocolHasNoDefinition(ObjCProtocolDecl *PDecl, ObjCProtocolDecl *&UndefinedProtocol) { if (!PDecl->hasDefinition() || PDecl->getDefinition()->isHidden()) { UndefinedProtocol = PDecl; return true; } for (auto *PI : PDecl->protocols()) if (NestedProtocolHasNoDefinition(PI, UndefinedProtocol)) { UndefinedProtocol = PI; return true; } return false; } /// FindProtocolDeclaration - This routine looks up protocols and /// issues an error if they are not declared. It returns list of /// protocol declarations in its 'Protocols' argument. void Sema::FindProtocolDeclaration(bool WarnOnDeclarations, bool ForObjCContainer, ArrayRef ProtocolId, SmallVectorImpl &Protocols) { for (const IdentifierLocPair &Pair : ProtocolId) { ObjCProtocolDecl *PDecl = LookupProtocol(Pair.first, Pair.second); if (!PDecl) { TypoCorrection Corrected = CorrectTypo( DeclarationNameInfo(Pair.first, Pair.second), LookupObjCProtocolName, TUScope, nullptr, llvm::make_unique>(), CTK_ErrorRecovery); if ((PDecl = Corrected.getCorrectionDeclAs())) diagnoseTypo(Corrected, PDiag(diag::err_undeclared_protocol_suggest) << Pair.first); } if (!PDecl) { Diag(Pair.second, diag::err_undeclared_protocol) << Pair.first; continue; } // If this is a forward protocol declaration, get its definition. if (!PDecl->isThisDeclarationADefinition() && PDecl->getDefinition()) PDecl = PDecl->getDefinition(); // For an objc container, delay protocol reference checking until after we // can set the objc decl as the availability context, otherwise check now. if (!ForObjCContainer) { (void)DiagnoseUseOfDecl(PDecl, Pair.second); } // If this is a forward declaration and we are supposed to warn in this // case, do it. // FIXME: Recover nicely in the hidden case. ObjCProtocolDecl *UndefinedProtocol; if (WarnOnDeclarations && NestedProtocolHasNoDefinition(PDecl, UndefinedProtocol)) { Diag(Pair.second, diag::warn_undef_protocolref) << Pair.first; Diag(UndefinedProtocol->getLocation(), diag::note_protocol_decl_undefined) << UndefinedProtocol; } Protocols.push_back(PDecl); } } namespace { // Callback to only accept typo corrections that are either // Objective-C protocols or valid Objective-C type arguments. class ObjCTypeArgOrProtocolValidatorCCC : public CorrectionCandidateCallback { ASTContext &Context; Sema::LookupNameKind LookupKind; public: ObjCTypeArgOrProtocolValidatorCCC(ASTContext &context, Sema::LookupNameKind lookupKind) : Context(context), LookupKind(lookupKind) { } bool ValidateCandidate(const TypoCorrection &candidate) override { // If we're allowed to find protocols and we have a protocol, accept it. if (LookupKind != Sema::LookupOrdinaryName) { if (candidate.getCorrectionDeclAs()) return true; } // If we're allowed to find type names and we have one, accept it. if (LookupKind != Sema::LookupObjCProtocolName) { // If we have a type declaration, we might accept this result. if (auto typeDecl = candidate.getCorrectionDeclAs()) { // If we found a tag declaration outside of C++, skip it. This // can happy because we look for any name when there is no // bias to protocol or type names. if (isa(typeDecl) && !Context.getLangOpts().CPlusPlus) return false; // Make sure the type is something we would accept as a type // argument. auto type = Context.getTypeDeclType(typeDecl); if (type->isObjCObjectPointerType() || type->isBlockPointerType() || type->isDependentType() || type->isObjCObjectType()) return true; return false; } // If we have an Objective-C class type, accept it; there will // be another fix to add the '*'. if (candidate.getCorrectionDeclAs()) return true; return false; } return false; } }; } // end anonymous namespace void Sema::DiagnoseTypeArgsAndProtocols(IdentifierInfo *ProtocolId, SourceLocation ProtocolLoc, IdentifierInfo *TypeArgId, SourceLocation TypeArgLoc, bool SelectProtocolFirst) { Diag(TypeArgLoc, diag::err_objc_type_args_and_protocols) << SelectProtocolFirst << TypeArgId << ProtocolId << SourceRange(ProtocolLoc); } void Sema::actOnObjCTypeArgsOrProtocolQualifiers( Scope *S, ParsedType baseType, SourceLocation lAngleLoc, ArrayRef identifiers, ArrayRef identifierLocs, SourceLocation rAngleLoc, SourceLocation &typeArgsLAngleLoc, SmallVectorImpl &typeArgs, SourceLocation &typeArgsRAngleLoc, SourceLocation &protocolLAngleLoc, SmallVectorImpl &protocols, SourceLocation &protocolRAngleLoc, bool warnOnIncompleteProtocols) { // Local function that updates the declaration specifiers with // protocol information. unsigned numProtocolsResolved = 0; auto resolvedAsProtocols = [&] { assert(numProtocolsResolved == identifiers.size() && "Unresolved protocols"); // Determine whether the base type is a parameterized class, in // which case we want to warn about typos such as // "NSArray" (that should be NSArray). ObjCInterfaceDecl *baseClass = nullptr; QualType base = GetTypeFromParser(baseType, nullptr); bool allAreTypeNames = false; SourceLocation firstClassNameLoc; if (!base.isNull()) { if (const auto *objcObjectType = base->getAs()) { baseClass = objcObjectType->getInterface(); if (baseClass) { if (auto typeParams = baseClass->getTypeParamList()) { if (typeParams->size() == numProtocolsResolved) { // Note that we should be looking for type names, too. allAreTypeNames = true; } } } } } for (unsigned i = 0, n = protocols.size(); i != n; ++i) { ObjCProtocolDecl *&proto = reinterpret_cast(protocols[i]); // For an objc container, delay protocol reference checking until after we // can set the objc decl as the availability context, otherwise check now. if (!warnOnIncompleteProtocols) { (void)DiagnoseUseOfDecl(proto, identifierLocs[i]); } // If this is a forward protocol declaration, get its definition. if (!proto->isThisDeclarationADefinition() && proto->getDefinition()) proto = proto->getDefinition(); // If this is a forward declaration and we are supposed to warn in this // case, do it. // FIXME: Recover nicely in the hidden case. ObjCProtocolDecl *forwardDecl = nullptr; if (warnOnIncompleteProtocols && NestedProtocolHasNoDefinition(proto, forwardDecl)) { Diag(identifierLocs[i], diag::warn_undef_protocolref) << proto->getDeclName(); Diag(forwardDecl->getLocation(), diag::note_protocol_decl_undefined) << forwardDecl; } // If everything this far has been a type name (and we care // about such things), check whether this name refers to a type // as well. if (allAreTypeNames) { if (auto *decl = LookupSingleName(S, identifiers[i], identifierLocs[i], LookupOrdinaryName)) { if (isa(decl)) { if (firstClassNameLoc.isInvalid()) firstClassNameLoc = identifierLocs[i]; } else if (!isa(decl)) { // Not a type. allAreTypeNames = false; } } else { allAreTypeNames = false; } } } // All of the protocols listed also have type names, and at least // one is an Objective-C class name. Check whether all of the // protocol conformances are declared by the base class itself, in // which case we warn. if (allAreTypeNames && firstClassNameLoc.isValid()) { llvm::SmallPtrSet knownProtocols; Context.CollectInheritedProtocols(baseClass, knownProtocols); bool allProtocolsDeclared = true; for (auto proto : protocols) { if (knownProtocols.count(static_cast(proto)) == 0) { allProtocolsDeclared = false; break; } } if (allProtocolsDeclared) { Diag(firstClassNameLoc, diag::warn_objc_redundant_qualified_class_type) << baseClass->getDeclName() << SourceRange(lAngleLoc, rAngleLoc) << FixItHint::CreateInsertion(getLocForEndOfToken(firstClassNameLoc), " *"); } } protocolLAngleLoc = lAngleLoc; protocolRAngleLoc = rAngleLoc; assert(protocols.size() == identifierLocs.size()); }; // Attempt to resolve all of the identifiers as protocols. for (unsigned i = 0, n = identifiers.size(); i != n; ++i) { ObjCProtocolDecl *proto = LookupProtocol(identifiers[i], identifierLocs[i]); protocols.push_back(proto); if (proto) ++numProtocolsResolved; } // If all of the names were protocols, these were protocol qualifiers. if (numProtocolsResolved == identifiers.size()) return resolvedAsProtocols(); // Attempt to resolve all of the identifiers as type names or // Objective-C class names. The latter is technically ill-formed, // but is probably something like \c NSArray missing the // \c*. typedef llvm::PointerUnion TypeOrClassDecl; SmallVector typeDecls; unsigned numTypeDeclsResolved = 0; for (unsigned i = 0, n = identifiers.size(); i != n; ++i) { NamedDecl *decl = LookupSingleName(S, identifiers[i], identifierLocs[i], LookupOrdinaryName); if (!decl) { typeDecls.push_back(TypeOrClassDecl()); continue; } if (auto typeDecl = dyn_cast(decl)) { typeDecls.push_back(typeDecl); ++numTypeDeclsResolved; continue; } if (auto objcClass = dyn_cast(decl)) { typeDecls.push_back(objcClass); ++numTypeDeclsResolved; continue; } typeDecls.push_back(TypeOrClassDecl()); } AttributeFactory attrFactory; // Local function that forms a reference to the given type or // Objective-C class declaration. auto resolveTypeReference = [&](TypeOrClassDecl typeDecl, SourceLocation loc) -> TypeResult { // Form declaration specifiers. They simply refer to the type. DeclSpec DS(attrFactory); const char* prevSpec; // unused unsigned diagID; // unused QualType type; if (auto *actualTypeDecl = typeDecl.dyn_cast()) type = Context.getTypeDeclType(actualTypeDecl); else type = Context.getObjCInterfaceType(typeDecl.get()); TypeSourceInfo *parsedTSInfo = Context.getTrivialTypeSourceInfo(type, loc); ParsedType parsedType = CreateParsedType(type, parsedTSInfo); DS.SetTypeSpecType(DeclSpec::TST_typename, loc, prevSpec, diagID, parsedType, Context.getPrintingPolicy()); // Use the identifier location for the type source range. DS.SetRangeStart(loc); DS.SetRangeEnd(loc); // Form the declarator. Declarator D(DS, Declarator::TypeNameContext); // If we have a typedef of an Objective-C class type that is missing a '*', // add the '*'. if (type->getAs()) { SourceLocation starLoc = getLocForEndOfToken(loc); ParsedAttributes parsedAttrs(attrFactory); D.AddTypeInfo(DeclaratorChunk::getPointer(/*typeQuals=*/0, starLoc, SourceLocation(), SourceLocation(), SourceLocation(), SourceLocation(), SourceLocation()), parsedAttrs, starLoc); // Diagnose the missing '*'. Diag(loc, diag::err_objc_type_arg_missing_star) << type << FixItHint::CreateInsertion(starLoc, " *"); } // Convert this to a type. return ActOnTypeName(S, D); }; // Local function that updates the declaration specifiers with // type argument information. auto resolvedAsTypeDecls = [&] { // We did not resolve these as protocols. protocols.clear(); assert(numTypeDeclsResolved == identifiers.size() && "Unresolved type decl"); // Map type declarations to type arguments. for (unsigned i = 0, n = identifiers.size(); i != n; ++i) { // Map type reference to a type. TypeResult type = resolveTypeReference(typeDecls[i], identifierLocs[i]); if (!type.isUsable()) { typeArgs.clear(); return; } typeArgs.push_back(type.get()); } typeArgsLAngleLoc = lAngleLoc; typeArgsRAngleLoc = rAngleLoc; }; // If all of the identifiers can be resolved as type names or // Objective-C class names, we have type arguments. if (numTypeDeclsResolved == identifiers.size()) return resolvedAsTypeDecls(); // Error recovery: some names weren't found, or we have a mix of // type and protocol names. Go resolve all of the unresolved names // and complain if we can't find a consistent answer. LookupNameKind lookupKind = LookupAnyName; for (unsigned i = 0, n = identifiers.size(); i != n; ++i) { // If we already have a protocol or type. Check whether it is the // right thing. if (protocols[i] || typeDecls[i]) { // If we haven't figured out whether we want types or protocols // yet, try to figure it out from this name. if (lookupKind == LookupAnyName) { // If this name refers to both a protocol and a type (e.g., \c // NSObject), don't conclude anything yet. if (protocols[i] && typeDecls[i]) continue; // Otherwise, let this name decide whether we'll be correcting // toward types or protocols. lookupKind = protocols[i] ? LookupObjCProtocolName : LookupOrdinaryName; continue; } // If we want protocols and we have a protocol, there's nothing // more to do. if (lookupKind == LookupObjCProtocolName && protocols[i]) continue; // If we want types and we have a type declaration, there's // nothing more to do. if (lookupKind == LookupOrdinaryName && typeDecls[i]) continue; // We have a conflict: some names refer to protocols and others // refer to types. DiagnoseTypeArgsAndProtocols(identifiers[0], identifierLocs[0], identifiers[i], identifierLocs[i], protocols[i] != nullptr); protocols.clear(); typeArgs.clear(); return; } // Perform typo correction on the name. TypoCorrection corrected = CorrectTypo( DeclarationNameInfo(identifiers[i], identifierLocs[i]), lookupKind, S, nullptr, llvm::make_unique(Context, lookupKind), CTK_ErrorRecovery); if (corrected) { // Did we find a protocol? if (auto proto = corrected.getCorrectionDeclAs()) { diagnoseTypo(corrected, PDiag(diag::err_undeclared_protocol_suggest) << identifiers[i]); lookupKind = LookupObjCProtocolName; protocols[i] = proto; ++numProtocolsResolved; continue; } // Did we find a type? if (auto typeDecl = corrected.getCorrectionDeclAs()) { diagnoseTypo(corrected, PDiag(diag::err_unknown_typename_suggest) << identifiers[i]); lookupKind = LookupOrdinaryName; typeDecls[i] = typeDecl; ++numTypeDeclsResolved; continue; } // Did we find an Objective-C class? if (auto objcClass = corrected.getCorrectionDeclAs()) { diagnoseTypo(corrected, PDiag(diag::err_unknown_type_or_class_name_suggest) << identifiers[i] << true); lookupKind = LookupOrdinaryName; typeDecls[i] = objcClass; ++numTypeDeclsResolved; continue; } } // We couldn't find anything. Diag(identifierLocs[i], (lookupKind == LookupAnyName ? diag::err_objc_type_arg_missing : lookupKind == LookupObjCProtocolName ? diag::err_undeclared_protocol : diag::err_unknown_typename)) << identifiers[i]; protocols.clear(); typeArgs.clear(); return; } // If all of the names were (corrected to) protocols, these were // protocol qualifiers. if (numProtocolsResolved == identifiers.size()) return resolvedAsProtocols(); // Otherwise, all of the names were (corrected to) types. assert(numTypeDeclsResolved == identifiers.size() && "Not all types?"); return resolvedAsTypeDecls(); } /// DiagnoseClassExtensionDupMethods - Check for duplicate declaration of /// a class method in its extension. /// void Sema::DiagnoseClassExtensionDupMethods(ObjCCategoryDecl *CAT, ObjCInterfaceDecl *ID) { if (!ID) return; // Possibly due to previous error llvm::DenseMap MethodMap; for (auto *MD : ID->methods()) MethodMap[MD->getSelector()] = MD; if (MethodMap.empty()) return; for (const auto *Method : CAT->methods()) { const ObjCMethodDecl *&PrevMethod = MethodMap[Method->getSelector()]; if (PrevMethod && (PrevMethod->isInstanceMethod() == Method->isInstanceMethod()) && !MatchTwoMethodDeclarations(Method, PrevMethod)) { Diag(Method->getLocation(), diag::err_duplicate_method_decl) << Method->getDeclName(); Diag(PrevMethod->getLocation(), diag::note_previous_declaration); } } } /// ActOnForwardProtocolDeclaration - Handle \@protocol foo; Sema::DeclGroupPtrTy Sema::ActOnForwardProtocolDeclaration(SourceLocation AtProtocolLoc, ArrayRef IdentList, AttributeList *attrList) { SmallVector DeclsInGroup; for (const IdentifierLocPair &IdentPair : IdentList) { IdentifierInfo *Ident = IdentPair.first; ObjCProtocolDecl *PrevDecl = LookupProtocol(Ident, IdentPair.second, ForRedeclaration); ObjCProtocolDecl *PDecl = ObjCProtocolDecl::Create(Context, CurContext, Ident, IdentPair.second, AtProtocolLoc, PrevDecl); PushOnScopeChains(PDecl, TUScope); CheckObjCDeclScope(PDecl); if (attrList) ProcessDeclAttributeList(TUScope, PDecl, attrList); if (PrevDecl) mergeDeclAttributes(PDecl, PrevDecl); DeclsInGroup.push_back(PDecl); } return BuildDeclaratorGroup(DeclsInGroup, false); } Decl *Sema:: ActOnStartCategoryInterface(SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName, SourceLocation ClassLoc, ObjCTypeParamList *typeParamList, IdentifierInfo *CategoryName, SourceLocation CategoryLoc, Decl * const *ProtoRefs, unsigned NumProtoRefs, const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc) { ObjCCategoryDecl *CDecl; ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true); /// Check that class of this category is already completely declared. if (!IDecl || RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl), diag::err_category_forward_interface, CategoryName == nullptr)) { // Create an invalid ObjCCategoryDecl to serve as context for // the enclosing method declarations. We mark the decl invalid // to make it clear that this isn't a valid AST. CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc, ClassLoc, CategoryLoc, CategoryName, IDecl, typeParamList); CDecl->setInvalidDecl(); CurContext->addDecl(CDecl); if (!IDecl) Diag(ClassLoc, diag::err_undef_interface) << ClassName; return ActOnObjCContainerStartDefinition(CDecl); } if (!CategoryName && IDecl->getImplementation()) { Diag(ClassLoc, diag::err_class_extension_after_impl) << ClassName; Diag(IDecl->getImplementation()->getLocation(), diag::note_implementation_declared); } if (CategoryName) { /// Check for duplicate interface declaration for this category if (ObjCCategoryDecl *Previous = IDecl->FindCategoryDeclaration(CategoryName)) { // Class extensions can be declared multiple times, categories cannot. Diag(CategoryLoc, diag::warn_dup_category_def) << ClassName << CategoryName; Diag(Previous->getLocation(), diag::note_previous_definition); } } // If we have a type parameter list, check it. if (typeParamList) { if (auto prevTypeParamList = IDecl->getTypeParamList()) { if (checkTypeParamListConsistency(*this, prevTypeParamList, typeParamList, CategoryName ? TypeParamListContext::Category : TypeParamListContext::Extension)) typeParamList = nullptr; } else { Diag(typeParamList->getLAngleLoc(), diag::err_objc_parameterized_category_nonclass) << (CategoryName != nullptr) << ClassName << typeParamList->getSourceRange(); typeParamList = nullptr; } } CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc, ClassLoc, CategoryLoc, CategoryName, IDecl, typeParamList); // FIXME: PushOnScopeChains? CurContext->addDecl(CDecl); if (NumProtoRefs) { diagnoseUseOfProtocols(*this, CDecl, (ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs, ProtoLocs); CDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs, ProtoLocs, Context); // Protocols in the class extension belong to the class. if (CDecl->IsClassExtension()) IDecl->mergeClassExtensionProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs, Context); } CheckObjCDeclScope(CDecl); return ActOnObjCContainerStartDefinition(CDecl); } /// ActOnStartCategoryImplementation - Perform semantic checks on the /// category implementation declaration and build an ObjCCategoryImplDecl /// object. Decl *Sema::ActOnStartCategoryImplementation( SourceLocation AtCatImplLoc, IdentifierInfo *ClassName, SourceLocation ClassLoc, IdentifierInfo *CatName, SourceLocation CatLoc) { ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true); ObjCCategoryDecl *CatIDecl = nullptr; if (IDecl && IDecl->hasDefinition()) { CatIDecl = IDecl->FindCategoryDeclaration(CatName); if (!CatIDecl) { // Category @implementation with no corresponding @interface. // Create and install one. CatIDecl = ObjCCategoryDecl::Create(Context, CurContext, AtCatImplLoc, ClassLoc, CatLoc, CatName, IDecl, /*typeParamList=*/nullptr); CatIDecl->setImplicit(); } } ObjCCategoryImplDecl *CDecl = ObjCCategoryImplDecl::Create(Context, CurContext, CatName, IDecl, ClassLoc, AtCatImplLoc, CatLoc); /// Check that class of this category is already completely declared. if (!IDecl) { Diag(ClassLoc, diag::err_undef_interface) << ClassName; CDecl->setInvalidDecl(); } else if (RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl), diag::err_undef_interface)) { CDecl->setInvalidDecl(); } // FIXME: PushOnScopeChains? CurContext->addDecl(CDecl); // If the interface is deprecated/unavailable, warn/error about it. if (IDecl) DiagnoseUseOfDecl(IDecl, ClassLoc); // If the interface has the objc_runtime_visible attribute, we // cannot implement a category for it. if (IDecl && IDecl->hasAttr()) { Diag(ClassLoc, diag::err_objc_runtime_visible_category) << IDecl->getDeclName(); } /// Check that CatName, category name, is not used in another implementation. if (CatIDecl) { if (CatIDecl->getImplementation()) { Diag(ClassLoc, diag::err_dup_implementation_category) << ClassName << CatName; Diag(CatIDecl->getImplementation()->getLocation(), diag::note_previous_definition); CDecl->setInvalidDecl(); } else { CatIDecl->setImplementation(CDecl); // Warn on implementating category of deprecated class under // -Wdeprecated-implementations flag. DiagnoseObjCImplementedDeprecations(*this, dyn_cast(IDecl), CDecl->getLocation(), 2); } } CheckObjCDeclScope(CDecl); return ActOnObjCContainerStartDefinition(CDecl); } Decl *Sema::ActOnStartClassImplementation( SourceLocation AtClassImplLoc, IdentifierInfo *ClassName, SourceLocation ClassLoc, IdentifierInfo *SuperClassname, SourceLocation SuperClassLoc) { ObjCInterfaceDecl *IDecl = nullptr; // Check for another declaration kind with the same name. NamedDecl *PrevDecl = LookupSingleName(TUScope, ClassName, ClassLoc, LookupOrdinaryName, ForRedeclaration); if (PrevDecl && !isa(PrevDecl)) { Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName; Diag(PrevDecl->getLocation(), diag::note_previous_definition); } else if ((IDecl = dyn_cast_or_null(PrevDecl))) { // FIXME: This will produce an error if the definition of the interface has // been imported from a module but is not visible. RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl), diag::warn_undef_interface); } else { // We did not find anything with the name ClassName; try to correct for // typos in the class name. TypoCorrection Corrected = CorrectTypo( DeclarationNameInfo(ClassName, ClassLoc), LookupOrdinaryName, TUScope, nullptr, llvm::make_unique(), CTK_NonError); if (Corrected.getCorrectionDeclAs()) { // Suggest the (potentially) correct interface name. Don't provide a // code-modification hint or use the typo name for recovery, because // this is just a warning. The program may actually be correct. diagnoseTypo(Corrected, PDiag(diag::warn_undef_interface_suggest) << ClassName, /*ErrorRecovery*/false); } else { Diag(ClassLoc, diag::warn_undef_interface) << ClassName; } } // Check that super class name is valid class name ObjCInterfaceDecl *SDecl = nullptr; if (SuperClassname) { // Check if a different kind of symbol declared in this scope. PrevDecl = LookupSingleName(TUScope, SuperClassname, SuperClassLoc, LookupOrdinaryName); if (PrevDecl && !isa(PrevDecl)) { Diag(SuperClassLoc, diag::err_redefinition_different_kind) << SuperClassname; Diag(PrevDecl->getLocation(), diag::note_previous_definition); } else { SDecl = dyn_cast_or_null(PrevDecl); if (SDecl && !SDecl->hasDefinition()) SDecl = nullptr; if (!SDecl) Diag(SuperClassLoc, diag::err_undef_superclass) << SuperClassname << ClassName; else if (IDecl && !declaresSameEntity(IDecl->getSuperClass(), SDecl)) { // This implementation and its interface do not have the same // super class. Diag(SuperClassLoc, diag::err_conflicting_super_class) << SDecl->getDeclName(); Diag(SDecl->getLocation(), diag::note_previous_definition); } } } if (!IDecl) { // Legacy case of @implementation with no corresponding @interface. // Build, chain & install the interface decl into the identifier. // FIXME: Do we support attributes on the @implementation? If so we should // copy them over. IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtClassImplLoc, ClassName, /*typeParamList=*/nullptr, /*PrevDecl=*/nullptr, ClassLoc, true); IDecl->startDefinition(); if (SDecl) { IDecl->setSuperClass(Context.getTrivialTypeSourceInfo( Context.getObjCInterfaceType(SDecl), SuperClassLoc)); IDecl->setEndOfDefinitionLoc(SuperClassLoc); } else { IDecl->setEndOfDefinitionLoc(ClassLoc); } PushOnScopeChains(IDecl, TUScope); } else { // Mark the interface as being completed, even if it was just as // @class ....; // declaration; the user cannot reopen it. if (!IDecl->hasDefinition()) IDecl->startDefinition(); } ObjCImplementationDecl* IMPDecl = ObjCImplementationDecl::Create(Context, CurContext, IDecl, SDecl, ClassLoc, AtClassImplLoc, SuperClassLoc); if (CheckObjCDeclScope(IMPDecl)) return ActOnObjCContainerStartDefinition(IMPDecl); // Check that there is no duplicate implementation of this class. if (IDecl->getImplementation()) { // FIXME: Don't leak everything! Diag(ClassLoc, diag::err_dup_implementation_class) << ClassName; Diag(IDecl->getImplementation()->getLocation(), diag::note_previous_definition); IMPDecl->setInvalidDecl(); } else { // add it to the list. IDecl->setImplementation(IMPDecl); PushOnScopeChains(IMPDecl, TUScope); // Warn on implementating deprecated class under // -Wdeprecated-implementations flag. DiagnoseObjCImplementedDeprecations(*this, dyn_cast(IDecl), IMPDecl->getLocation(), 1); } // If the superclass has the objc_runtime_visible attribute, we // cannot implement a subclass of it. if (IDecl->getSuperClass() && IDecl->getSuperClass()->hasAttr()) { Diag(ClassLoc, diag::err_objc_runtime_visible_subclass) << IDecl->getDeclName() << IDecl->getSuperClass()->getDeclName(); } return ActOnObjCContainerStartDefinition(IMPDecl); } Sema::DeclGroupPtrTy Sema::ActOnFinishObjCImplementation(Decl *ObjCImpDecl, ArrayRef Decls) { SmallVector DeclsInGroup; DeclsInGroup.reserve(Decls.size() + 1); for (unsigned i = 0, e = Decls.size(); i != e; ++i) { Decl *Dcl = Decls[i]; if (!Dcl) continue; if (Dcl->getDeclContext()->isFileContext()) Dcl->setTopLevelDeclInObjCContainer(); DeclsInGroup.push_back(Dcl); } DeclsInGroup.push_back(ObjCImpDecl); return BuildDeclaratorGroup(DeclsInGroup, false); } void Sema::CheckImplementationIvars(ObjCImplementationDecl *ImpDecl, ObjCIvarDecl **ivars, unsigned numIvars, SourceLocation RBrace) { assert(ImpDecl && "missing implementation decl"); ObjCInterfaceDecl* IDecl = ImpDecl->getClassInterface(); if (!IDecl) return; /// Check case of non-existing \@interface decl. /// (legacy objective-c \@implementation decl without an \@interface decl). /// Add implementations's ivar to the synthesize class's ivar list. if (IDecl->isImplicitInterfaceDecl()) { IDecl->setEndOfDefinitionLoc(RBrace); // Add ivar's to class's DeclContext. for (unsigned i = 0, e = numIvars; i != e; ++i) { ivars[i]->setLexicalDeclContext(ImpDecl); IDecl->makeDeclVisibleInContext(ivars[i]); ImpDecl->addDecl(ivars[i]); } return; } // If implementation has empty ivar list, just return. if (numIvars == 0) return; assert(ivars && "missing @implementation ivars"); if (LangOpts.ObjCRuntime.isNonFragile()) { if (ImpDecl->getSuperClass()) Diag(ImpDecl->getLocation(), diag::warn_on_superclass_use); for (unsigned i = 0; i < numIvars; i++) { ObjCIvarDecl* ImplIvar = ivars[i]; if (const ObjCIvarDecl *ClsIvar = IDecl->getIvarDecl(ImplIvar->getIdentifier())) { Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration); Diag(ClsIvar->getLocation(), diag::note_previous_definition); continue; } // Check class extensions (unnamed categories) for duplicate ivars. for (const auto *CDecl : IDecl->visible_extensions()) { if (const ObjCIvarDecl *ClsExtIvar = CDecl->getIvarDecl(ImplIvar->getIdentifier())) { Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration); Diag(ClsExtIvar->getLocation(), diag::note_previous_definition); continue; } } // Instance ivar to Implementation's DeclContext. ImplIvar->setLexicalDeclContext(ImpDecl); IDecl->makeDeclVisibleInContext(ImplIvar); ImpDecl->addDecl(ImplIvar); } return; } // Check interface's Ivar list against those in the implementation. // names and types must match. // unsigned j = 0; ObjCInterfaceDecl::ivar_iterator IVI = IDecl->ivar_begin(), IVE = IDecl->ivar_end(); for (; numIvars > 0 && IVI != IVE; ++IVI) { ObjCIvarDecl* ImplIvar = ivars[j++]; ObjCIvarDecl* ClsIvar = *IVI; assert (ImplIvar && "missing implementation ivar"); assert (ClsIvar && "missing class ivar"); // First, make sure the types match. if (!Context.hasSameType(ImplIvar->getType(), ClsIvar->getType())) { Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_type) << ImplIvar->getIdentifier() << ImplIvar->getType() << ClsIvar->getType(); Diag(ClsIvar->getLocation(), diag::note_previous_definition); } else if (ImplIvar->isBitField() && ClsIvar->isBitField() && ImplIvar->getBitWidthValue(Context) != ClsIvar->getBitWidthValue(Context)) { Diag(ImplIvar->getBitWidth()->getLocStart(), diag::err_conflicting_ivar_bitwidth) << ImplIvar->getIdentifier(); Diag(ClsIvar->getBitWidth()->getLocStart(), diag::note_previous_definition); } // Make sure the names are identical. if (ImplIvar->getIdentifier() != ClsIvar->getIdentifier()) { Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_name) << ImplIvar->getIdentifier() << ClsIvar->getIdentifier(); Diag(ClsIvar->getLocation(), diag::note_previous_definition); } --numIvars; } if (numIvars > 0) Diag(ivars[j]->getLocation(), diag::err_inconsistent_ivar_count); else if (IVI != IVE) Diag(IVI->getLocation(), diag::err_inconsistent_ivar_count); } static void WarnUndefinedMethod(Sema &S, SourceLocation ImpLoc, ObjCMethodDecl *method, bool &IncompleteImpl, unsigned DiagID, NamedDecl *NeededFor = nullptr) { // No point warning no definition of method which is 'unavailable'. switch (method->getAvailability()) { case AR_Available: case AR_Deprecated: break; // Don't warn about unavailable or not-yet-introduced methods. case AR_NotYetIntroduced: case AR_Unavailable: return; } // FIXME: For now ignore 'IncompleteImpl'. // Previously we grouped all unimplemented methods under a single // warning, but some users strongly voiced that they would prefer // separate warnings. We will give that approach a try, as that // matches what we do with protocols. { const Sema::SemaDiagnosticBuilder &B = S.Diag(ImpLoc, DiagID); B << method; if (NeededFor) B << NeededFor; } // Issue a note to the original declaration. SourceLocation MethodLoc = method->getLocStart(); if (MethodLoc.isValid()) S.Diag(MethodLoc, diag::note_method_declared_at) << method; } /// Determines if type B can be substituted for type A. Returns true if we can /// guarantee that anything that the user will do to an object of type A can /// also be done to an object of type B. This is trivially true if the two /// types are the same, or if B is a subclass of A. It becomes more complex /// in cases where protocols are involved. /// /// Object types in Objective-C describe the minimum requirements for an /// object, rather than providing a complete description of a type. For /// example, if A is a subclass of B, then B* may refer to an instance of A. /// The principle of substitutability means that we may use an instance of A /// anywhere that we may use an instance of B - it will implement all of the /// ivars of B and all of the methods of B. /// /// This substitutability is important when type checking methods, because /// the implementation may have stricter type definitions than the interface. /// The interface specifies minimum requirements, but the implementation may /// have more accurate ones. For example, a method may privately accept /// instances of B, but only publish that it accepts instances of A. Any /// object passed to it will be type checked against B, and so will implicitly /// by a valid A*. Similarly, a method may return a subclass of the class that /// it is declared as returning. /// /// This is most important when considering subclassing. A method in a /// subclass must accept any object as an argument that its superclass's /// implementation accepts. It may, however, accept a more general type /// without breaking substitutability (i.e. you can still use the subclass /// anywhere that you can use the superclass, but not vice versa). The /// converse requirement applies to return types: the return type for a /// subclass method must be a valid object of the kind that the superclass /// advertises, but it may be specified more accurately. This avoids the need /// for explicit down-casting by callers. /// /// Note: This is a stricter requirement than for assignment. static bool isObjCTypeSubstitutable(ASTContext &Context, const ObjCObjectPointerType *A, const ObjCObjectPointerType *B, bool rejectId) { // Reject a protocol-unqualified id. if (rejectId && B->isObjCIdType()) return false; // If B is a qualified id, then A must also be a qualified id and it must // implement all of the protocols in B. It may not be a qualified class. // For example, MyClass can be assigned to id, but MyClass is a // stricter definition so it is not substitutable for id. if (B->isObjCQualifiedIdType()) { return A->isObjCQualifiedIdType() && Context.ObjCQualifiedIdTypesAreCompatible(QualType(A, 0), QualType(B,0), false); } /* // id is a special type that bypasses type checking completely. We want a // warning when it is used in one place but not another. if (C.isObjCIdType(A) || C.isObjCIdType(B)) return false; // If B is a qualified id, then A must also be a qualified id (which it isn't // if we've got this far) if (B->isObjCQualifiedIdType()) return false; */ // Now we know that A and B are (potentially-qualified) class types. The // normal rules for assignment apply. return Context.canAssignObjCInterfaces(A, B); } static SourceRange getTypeRange(TypeSourceInfo *TSI) { return (TSI ? TSI->getTypeLoc().getSourceRange() : SourceRange()); } /// Determine whether two set of Objective-C declaration qualifiers conflict. static bool objcModifiersConflict(Decl::ObjCDeclQualifier x, Decl::ObjCDeclQualifier y) { return (x & ~Decl::OBJC_TQ_CSNullability) != (y & ~Decl::OBJC_TQ_CSNullability); } static bool CheckMethodOverrideReturn(Sema &S, ObjCMethodDecl *MethodImpl, ObjCMethodDecl *MethodDecl, bool IsProtocolMethodDecl, bool IsOverridingMode, bool Warn) { if (IsProtocolMethodDecl && objcModifiersConflict(MethodDecl->getObjCDeclQualifier(), MethodImpl->getObjCDeclQualifier())) { if (Warn) { S.Diag(MethodImpl->getLocation(), (IsOverridingMode ? diag::warn_conflicting_overriding_ret_type_modifiers : diag::warn_conflicting_ret_type_modifiers)) << MethodImpl->getDeclName() << MethodImpl->getReturnTypeSourceRange(); S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration) << MethodDecl->getReturnTypeSourceRange(); } else return false; } if (Warn && IsOverridingMode && !isa(MethodImpl->getDeclContext()) && !S.Context.hasSameNullabilityTypeQualifier(MethodImpl->getReturnType(), MethodDecl->getReturnType(), false)) { auto nullabilityMethodImpl = *MethodImpl->getReturnType()->getNullability(S.Context); auto nullabilityMethodDecl = *MethodDecl->getReturnType()->getNullability(S.Context); S.Diag(MethodImpl->getLocation(), diag::warn_conflicting_nullability_attr_overriding_ret_types) << DiagNullabilityKind( nullabilityMethodImpl, ((MethodImpl->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) != 0)) << DiagNullabilityKind( nullabilityMethodDecl, ((MethodDecl->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) != 0)); S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration); } if (S.Context.hasSameUnqualifiedType(MethodImpl->getReturnType(), MethodDecl->getReturnType())) return true; if (!Warn) return false; unsigned DiagID = IsOverridingMode ? diag::warn_conflicting_overriding_ret_types : diag::warn_conflicting_ret_types; // Mismatches between ObjC pointers go into a different warning // category, and sometimes they're even completely whitelisted. if (const ObjCObjectPointerType *ImplPtrTy = MethodImpl->getReturnType()->getAs()) { if (const ObjCObjectPointerType *IfacePtrTy = MethodDecl->getReturnType()->getAs()) { // Allow non-matching return types as long as they don't violate // the principle of substitutability. Specifically, we permit // return types that are subclasses of the declared return type, // or that are more-qualified versions of the declared type. if (isObjCTypeSubstitutable(S.Context, IfacePtrTy, ImplPtrTy, false)) return false; DiagID = IsOverridingMode ? diag::warn_non_covariant_overriding_ret_types : diag::warn_non_covariant_ret_types; } } S.Diag(MethodImpl->getLocation(), DiagID) << MethodImpl->getDeclName() << MethodDecl->getReturnType() << MethodImpl->getReturnType() << MethodImpl->getReturnTypeSourceRange(); S.Diag(MethodDecl->getLocation(), IsOverridingMode ? diag::note_previous_declaration : diag::note_previous_definition) << MethodDecl->getReturnTypeSourceRange(); return false; } static bool CheckMethodOverrideParam(Sema &S, ObjCMethodDecl *MethodImpl, ObjCMethodDecl *MethodDecl, ParmVarDecl *ImplVar, ParmVarDecl *IfaceVar, bool IsProtocolMethodDecl, bool IsOverridingMode, bool Warn) { if (IsProtocolMethodDecl && objcModifiersConflict(ImplVar->getObjCDeclQualifier(), IfaceVar->getObjCDeclQualifier())) { if (Warn) { if (IsOverridingMode) S.Diag(ImplVar->getLocation(), diag::warn_conflicting_overriding_param_modifiers) << getTypeRange(ImplVar->getTypeSourceInfo()) << MethodImpl->getDeclName(); else S.Diag(ImplVar->getLocation(), diag::warn_conflicting_param_modifiers) << getTypeRange(ImplVar->getTypeSourceInfo()) << MethodImpl->getDeclName(); S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration) << getTypeRange(IfaceVar->getTypeSourceInfo()); } else return false; } QualType ImplTy = ImplVar->getType(); QualType IfaceTy = IfaceVar->getType(); if (Warn && IsOverridingMode && !isa(MethodImpl->getDeclContext()) && !S.Context.hasSameNullabilityTypeQualifier(ImplTy, IfaceTy, true)) { S.Diag(ImplVar->getLocation(), diag::warn_conflicting_nullability_attr_overriding_param_types) << DiagNullabilityKind( *ImplTy->getNullability(S.Context), ((ImplVar->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) != 0)) << DiagNullabilityKind( *IfaceTy->getNullability(S.Context), ((IfaceVar->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) != 0)); S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration); } if (S.Context.hasSameUnqualifiedType(ImplTy, IfaceTy)) return true; if (!Warn) return false; unsigned DiagID = IsOverridingMode ? diag::warn_conflicting_overriding_param_types : diag::warn_conflicting_param_types; // Mismatches between ObjC pointers go into a different warning // category, and sometimes they're even completely whitelisted. if (const ObjCObjectPointerType *ImplPtrTy = ImplTy->getAs()) { if (const ObjCObjectPointerType *IfacePtrTy = IfaceTy->getAs()) { // Allow non-matching argument types as long as they don't // violate the principle of substitutability. Specifically, the // implementation must accept any objects that the superclass // accepts, however it may also accept others. if (isObjCTypeSubstitutable(S.Context, ImplPtrTy, IfacePtrTy, true)) return false; DiagID = IsOverridingMode ? diag::warn_non_contravariant_overriding_param_types : diag::warn_non_contravariant_param_types; } } S.Diag(ImplVar->getLocation(), DiagID) << getTypeRange(ImplVar->getTypeSourceInfo()) << MethodImpl->getDeclName() << IfaceTy << ImplTy; S.Diag(IfaceVar->getLocation(), (IsOverridingMode ? diag::note_previous_declaration : diag::note_previous_definition)) << getTypeRange(IfaceVar->getTypeSourceInfo()); return false; } /// In ARC, check whether the conventional meanings of the two methods /// match. If they don't, it's a hard error. static bool checkMethodFamilyMismatch(Sema &S, ObjCMethodDecl *impl, ObjCMethodDecl *decl) { ObjCMethodFamily implFamily = impl->getMethodFamily(); ObjCMethodFamily declFamily = decl->getMethodFamily(); if (implFamily == declFamily) return false; // Since conventions are sorted by selector, the only possibility is // that the types differ enough to cause one selector or the other // to fall out of the family. assert(implFamily == OMF_None || declFamily == OMF_None); // No further diagnostics required on invalid declarations. if (impl->isInvalidDecl() || decl->isInvalidDecl()) return true; const ObjCMethodDecl *unmatched = impl; ObjCMethodFamily family = declFamily; unsigned errorID = diag::err_arc_lost_method_convention; unsigned noteID = diag::note_arc_lost_method_convention; if (declFamily == OMF_None) { unmatched = decl; family = implFamily; errorID = diag::err_arc_gained_method_convention; noteID = diag::note_arc_gained_method_convention; } // Indexes into a %select clause in the diagnostic. enum FamilySelector { F_alloc, F_copy, F_mutableCopy = F_copy, F_init, F_new }; FamilySelector familySelector = FamilySelector(); switch (family) { case OMF_None: llvm_unreachable("logic error, no method convention"); case OMF_retain: case OMF_release: case OMF_autorelease: case OMF_dealloc: case OMF_finalize: case OMF_retainCount: case OMF_self: case OMF_initialize: case OMF_performSelector: // Mismatches for these methods don't change ownership // conventions, so we don't care. return false; case OMF_init: familySelector = F_init; break; case OMF_alloc: familySelector = F_alloc; break; case OMF_copy: familySelector = F_copy; break; case OMF_mutableCopy: familySelector = F_mutableCopy; break; case OMF_new: familySelector = F_new; break; } enum ReasonSelector { R_NonObjectReturn, R_UnrelatedReturn }; ReasonSelector reasonSelector; // The only reason these methods don't fall within their families is // due to unusual result types. if (unmatched->getReturnType()->isObjCObjectPointerType()) { reasonSelector = R_UnrelatedReturn; } else { reasonSelector = R_NonObjectReturn; } S.Diag(impl->getLocation(), errorID) << int(familySelector) << int(reasonSelector); S.Diag(decl->getLocation(), noteID) << int(familySelector) << int(reasonSelector); return true; } void Sema::WarnConflictingTypedMethods(ObjCMethodDecl *ImpMethodDecl, ObjCMethodDecl *MethodDecl, bool IsProtocolMethodDecl) { if (getLangOpts().ObjCAutoRefCount && checkMethodFamilyMismatch(*this, ImpMethodDecl, MethodDecl)) return; CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl, IsProtocolMethodDecl, false, true); for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(), IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(), EF = MethodDecl->param_end(); IM != EM && IF != EF; ++IM, ++IF) { CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl, *IM, *IF, IsProtocolMethodDecl, false, true); } if (ImpMethodDecl->isVariadic() != MethodDecl->isVariadic()) { Diag(ImpMethodDecl->getLocation(), diag::warn_conflicting_variadic); Diag(MethodDecl->getLocation(), diag::note_previous_declaration); } } void Sema::CheckConflictingOverridingMethod(ObjCMethodDecl *Method, ObjCMethodDecl *Overridden, bool IsProtocolMethodDecl) { CheckMethodOverrideReturn(*this, Method, Overridden, IsProtocolMethodDecl, true, true); for (ObjCMethodDecl::param_iterator IM = Method->param_begin(), IF = Overridden->param_begin(), EM = Method->param_end(), EF = Overridden->param_end(); IM != EM && IF != EF; ++IM, ++IF) { CheckMethodOverrideParam(*this, Method, Overridden, *IM, *IF, IsProtocolMethodDecl, true, true); } if (Method->isVariadic() != Overridden->isVariadic()) { Diag(Method->getLocation(), diag::warn_conflicting_overriding_variadic); Diag(Overridden->getLocation(), diag::note_previous_declaration); } } /// WarnExactTypedMethods - This routine issues a warning if method /// implementation declaration matches exactly that of its declaration. void Sema::WarnExactTypedMethods(ObjCMethodDecl *ImpMethodDecl, ObjCMethodDecl *MethodDecl, bool IsProtocolMethodDecl) { // don't issue warning when protocol method is optional because primary // class is not required to implement it and it is safe for protocol // to implement it. if (MethodDecl->getImplementationControl() == ObjCMethodDecl::Optional) return; // don't issue warning when primary class's method is // depecated/unavailable. if (MethodDecl->hasAttr() || MethodDecl->hasAttr()) return; bool match = CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl, IsProtocolMethodDecl, false, false); if (match) for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(), IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(), EF = MethodDecl->param_end(); IM != EM && IF != EF; ++IM, ++IF) { match = CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl, *IM, *IF, IsProtocolMethodDecl, false, false); if (!match) break; } if (match) match = (ImpMethodDecl->isVariadic() == MethodDecl->isVariadic()); if (match) match = !(MethodDecl->isClassMethod() && MethodDecl->getSelector() == GetNullarySelector("load", Context)); if (match) { Diag(ImpMethodDecl->getLocation(), diag::warn_category_method_impl_match); Diag(MethodDecl->getLocation(), diag::note_method_declared_at) << MethodDecl->getDeclName(); } } /// FIXME: Type hierarchies in Objective-C can be deep. We could most likely /// improve the efficiency of selector lookups and type checking by associating /// with each protocol / interface / category the flattened instance tables. If /// we used an immutable set to keep the table then it wouldn't add significant /// memory cost and it would be handy for lookups. typedef llvm::DenseSet ProtocolNameSet; typedef std::unique_ptr LazyProtocolNameSet; static void findProtocolsWithExplicitImpls(const ObjCProtocolDecl *PDecl, ProtocolNameSet &PNS) { if (PDecl->hasAttr()) PNS.insert(PDecl->getIdentifier()); for (const auto *PI : PDecl->protocols()) findProtocolsWithExplicitImpls(PI, PNS); } /// Recursively populates a set with all conformed protocols in a class /// hierarchy that have the 'objc_protocol_requires_explicit_implementation' /// attribute. static void findProtocolsWithExplicitImpls(const ObjCInterfaceDecl *Super, ProtocolNameSet &PNS) { if (!Super) return; for (const auto *I : Super->all_referenced_protocols()) findProtocolsWithExplicitImpls(I, PNS); findProtocolsWithExplicitImpls(Super->getSuperClass(), PNS); } /// CheckProtocolMethodDefs - This routine checks unimplemented methods /// Declared in protocol, and those referenced by it. static void CheckProtocolMethodDefs(Sema &S, SourceLocation ImpLoc, ObjCProtocolDecl *PDecl, bool& IncompleteImpl, const Sema::SelectorSet &InsMap, const Sema::SelectorSet &ClsMap, ObjCContainerDecl *CDecl, LazyProtocolNameSet &ProtocolsExplictImpl) { ObjCCategoryDecl *C = dyn_cast(CDecl); ObjCInterfaceDecl *IDecl = C ? C->getClassInterface() : dyn_cast(CDecl); assert (IDecl && "CheckProtocolMethodDefs - IDecl is null"); ObjCInterfaceDecl *Super = IDecl->getSuperClass(); ObjCInterfaceDecl *NSIDecl = nullptr; // If this protocol is marked 'objc_protocol_requires_explicit_implementation' // then we should check if any class in the super class hierarchy also // conforms to this protocol, either directly or via protocol inheritance. // If so, we can skip checking this protocol completely because we // know that a parent class already satisfies this protocol. // // Note: we could generalize this logic for all protocols, and merely // add the limit on looking at the super class chain for just // specially marked protocols. This may be a good optimization. This // change is restricted to 'objc_protocol_requires_explicit_implementation' // protocols for now for controlled evaluation. if (PDecl->hasAttr()) { if (!ProtocolsExplictImpl) { ProtocolsExplictImpl.reset(new ProtocolNameSet); findProtocolsWithExplicitImpls(Super, *ProtocolsExplictImpl); } if (ProtocolsExplictImpl->find(PDecl->getIdentifier()) != ProtocolsExplictImpl->end()) return; // If no super class conforms to the protocol, we should not search // for methods in the super class to implicitly satisfy the protocol. Super = nullptr; } if (S.getLangOpts().ObjCRuntime.isNeXTFamily()) { // check to see if class implements forwardInvocation method and objects // of this class are derived from 'NSProxy' so that to forward requests // from one object to another. // Under such conditions, which means that every method possible is // implemented in the class, we should not issue "Method definition not // found" warnings. // FIXME: Use a general GetUnarySelector method for this. IdentifierInfo* II = &S.Context.Idents.get("forwardInvocation"); Selector fISelector = S.Context.Selectors.getSelector(1, &II); if (InsMap.count(fISelector)) // Is IDecl derived from 'NSProxy'? If so, no instance methods // need be implemented in the implementation. NSIDecl = IDecl->lookupInheritedClass(&S.Context.Idents.get("NSProxy")); } // If this is a forward protocol declaration, get its definition. if (!PDecl->isThisDeclarationADefinition() && PDecl->getDefinition()) PDecl = PDecl->getDefinition(); // If a method lookup fails locally we still need to look and see if // the method was implemented by a base class or an inherited // protocol. This lookup is slow, but occurs rarely in correct code // and otherwise would terminate in a warning. // check unimplemented instance methods. if (!NSIDecl) for (auto *method : PDecl->instance_methods()) { if (method->getImplementationControl() != ObjCMethodDecl::Optional && !method->isPropertyAccessor() && !InsMap.count(method->getSelector()) && (!Super || !Super->lookupMethod(method->getSelector(), true /* instance */, false /* shallowCategory */, true /* followsSuper */, nullptr /* category */))) { // If a method is not implemented in the category implementation but // has been declared in its primary class, superclass, // or in one of their protocols, no need to issue the warning. // This is because method will be implemented in the primary class // or one of its super class implementation. // Ugly, but necessary. Method declared in protcol might have // have been synthesized due to a property declared in the class which // uses the protocol. if (ObjCMethodDecl *MethodInClass = IDecl->lookupMethod(method->getSelector(), true /* instance */, true /* shallowCategoryLookup */, false /* followSuper */)) if (C || MethodInClass->isPropertyAccessor()) continue; unsigned DIAG = diag::warn_unimplemented_protocol_method; if (!S.Diags.isIgnored(DIAG, ImpLoc)) { WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG, PDecl); } } } // check unimplemented class methods for (auto *method : PDecl->class_methods()) { if (method->getImplementationControl() != ObjCMethodDecl::Optional && !ClsMap.count(method->getSelector()) && (!Super || !Super->lookupMethod(method->getSelector(), false /* class method */, false /* shallowCategoryLookup */, true /* followSuper */, nullptr /* category */))) { // See above comment for instance method lookups. if (C && IDecl->lookupMethod(method->getSelector(), false /* class */, true /* shallowCategoryLookup */, false /* followSuper */)) continue; unsigned DIAG = diag::warn_unimplemented_protocol_method; if (!S.Diags.isIgnored(DIAG, ImpLoc)) { WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG, PDecl); } } } // Check on this protocols's referenced protocols, recursively. for (auto *PI : PDecl->protocols()) CheckProtocolMethodDefs(S, ImpLoc, PI, IncompleteImpl, InsMap, ClsMap, CDecl, ProtocolsExplictImpl); } /// MatchAllMethodDeclarations - Check methods declared in interface /// or protocol against those declared in their implementations. /// void Sema::MatchAllMethodDeclarations(const SelectorSet &InsMap, const SelectorSet &ClsMap, SelectorSet &InsMapSeen, SelectorSet &ClsMapSeen, ObjCImplDecl* IMPDecl, ObjCContainerDecl* CDecl, bool &IncompleteImpl, bool ImmediateClass, bool WarnCategoryMethodImpl) { // Check and see if instance methods in class interface have been // implemented in the implementation class. If so, their types match. for (auto *I : CDecl->instance_methods()) { if (!InsMapSeen.insert(I->getSelector()).second) continue; if (!I->isPropertyAccessor() && !InsMap.count(I->getSelector())) { if (ImmediateClass) WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl, diag::warn_undef_method_impl); continue; } else { ObjCMethodDecl *ImpMethodDecl = IMPDecl->getInstanceMethod(I->getSelector()); assert(CDecl->getInstanceMethod(I->getSelector()) && "Expected to find the method through lookup as well"); // ImpMethodDecl may be null as in a @dynamic property. if (ImpMethodDecl) { if (!WarnCategoryMethodImpl) WarnConflictingTypedMethods(ImpMethodDecl, I, isa(CDecl)); else if (!I->isPropertyAccessor()) WarnExactTypedMethods(ImpMethodDecl, I, isa(CDecl)); } } } // Check and see if class methods in class interface have been // implemented in the implementation class. If so, their types match. for (auto *I : CDecl->class_methods()) { if (!ClsMapSeen.insert(I->getSelector()).second) continue; if (!I->isPropertyAccessor() && !ClsMap.count(I->getSelector())) { if (ImmediateClass) WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl, diag::warn_undef_method_impl); } else { ObjCMethodDecl *ImpMethodDecl = IMPDecl->getClassMethod(I->getSelector()); assert(CDecl->getClassMethod(I->getSelector()) && "Expected to find the method through lookup as well"); // ImpMethodDecl may be null as in a @dynamic property. if (ImpMethodDecl) { if (!WarnCategoryMethodImpl) WarnConflictingTypedMethods(ImpMethodDecl, I, isa(CDecl)); else if (!I->isPropertyAccessor()) WarnExactTypedMethods(ImpMethodDecl, I, isa(CDecl)); } } } if (ObjCProtocolDecl *PD = dyn_cast (CDecl)) { // Also, check for methods declared in protocols inherited by // this protocol. for (auto *PI : PD->protocols()) MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen, IMPDecl, PI, IncompleteImpl, false, WarnCategoryMethodImpl); } if (ObjCInterfaceDecl *I = dyn_cast (CDecl)) { // when checking that methods in implementation match their declaration, // i.e. when WarnCategoryMethodImpl is false, check declarations in class // extension; as well as those in categories. if (!WarnCategoryMethodImpl) { for (auto *Cat : I->visible_categories()) MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen, IMPDecl, Cat, IncompleteImpl, ImmediateClass && Cat->IsClassExtension(), WarnCategoryMethodImpl); } else { // Also methods in class extensions need be looked at next. for (auto *Ext : I->visible_extensions()) MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen, IMPDecl, Ext, IncompleteImpl, false, WarnCategoryMethodImpl); } // Check for any implementation of a methods declared in protocol. for (auto *PI : I->all_referenced_protocols()) MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen, IMPDecl, PI, IncompleteImpl, false, WarnCategoryMethodImpl); // FIXME. For now, we are not checking for extact match of methods // in category implementation and its primary class's super class. if (!WarnCategoryMethodImpl && I->getSuperClass()) MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen, IMPDecl, I->getSuperClass(), IncompleteImpl, false); } } /// CheckCategoryVsClassMethodMatches - Checks that methods implemented in /// category matches with those implemented in its primary class and /// warns each time an exact match is found. void Sema::CheckCategoryVsClassMethodMatches( ObjCCategoryImplDecl *CatIMPDecl) { // Get category's primary class. ObjCCategoryDecl *CatDecl = CatIMPDecl->getCategoryDecl(); if (!CatDecl) return; ObjCInterfaceDecl *IDecl = CatDecl->getClassInterface(); if (!IDecl) return; ObjCInterfaceDecl *SuperIDecl = IDecl->getSuperClass(); SelectorSet InsMap, ClsMap; for (const auto *I : CatIMPDecl->instance_methods()) { Selector Sel = I->getSelector(); // When checking for methods implemented in the category, skip over // those declared in category class's super class. This is because // the super class must implement the method. if (SuperIDecl && SuperIDecl->lookupMethod(Sel, true)) continue; InsMap.insert(Sel); } for (const auto *I : CatIMPDecl->class_methods()) { Selector Sel = I->getSelector(); if (SuperIDecl && SuperIDecl->lookupMethod(Sel, false)) continue; ClsMap.insert(Sel); } if (InsMap.empty() && ClsMap.empty()) return; SelectorSet InsMapSeen, ClsMapSeen; bool IncompleteImpl = false; MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen, CatIMPDecl, IDecl, IncompleteImpl, false, true /*WarnCategoryMethodImpl*/); } void Sema::ImplMethodsVsClassMethods(Scope *S, ObjCImplDecl* IMPDecl, ObjCContainerDecl* CDecl, bool IncompleteImpl) { SelectorSet InsMap; // Check and see if instance methods in class interface have been // implemented in the implementation class. for (const auto *I : IMPDecl->instance_methods()) InsMap.insert(I->getSelector()); // Add the selectors for getters/setters of @dynamic properties. for (const auto *PImpl : IMPDecl->property_impls()) { // We only care about @dynamic implementations. if (PImpl->getPropertyImplementation() != ObjCPropertyImplDecl::Dynamic) continue; const auto *P = PImpl->getPropertyDecl(); if (!P) continue; InsMap.insert(P->getGetterName()); if (!P->getSetterName().isNull()) InsMap.insert(P->getSetterName()); } // Check and see if properties declared in the interface have either 1) // an implementation or 2) there is a @synthesize/@dynamic implementation // of the property in the @implementation. if (const ObjCInterfaceDecl *IDecl = dyn_cast(CDecl)) { bool SynthesizeProperties = LangOpts.ObjCDefaultSynthProperties && LangOpts.ObjCRuntime.isNonFragile() && !IDecl->isObjCRequiresPropertyDefs(); DiagnoseUnimplementedProperties(S, IMPDecl, CDecl, SynthesizeProperties); } // Diagnose null-resettable synthesized setters. diagnoseNullResettableSynthesizedSetters(IMPDecl); SelectorSet ClsMap; for (const auto *I : IMPDecl->class_methods()) ClsMap.insert(I->getSelector()); // Check for type conflict of methods declared in a class/protocol and // its implementation; if any. SelectorSet InsMapSeen, ClsMapSeen; MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen, IMPDecl, CDecl, IncompleteImpl, true); // check all methods implemented in category against those declared // in its primary class. if (ObjCCategoryImplDecl *CatDecl = dyn_cast(IMPDecl)) CheckCategoryVsClassMethodMatches(CatDecl); // Check the protocol list for unimplemented methods in the @implementation // class. // Check and see if class methods in class interface have been // implemented in the implementation class. LazyProtocolNameSet ExplicitImplProtocols; if (ObjCInterfaceDecl *I = dyn_cast (CDecl)) { for (auto *PI : I->all_referenced_protocols()) CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), PI, IncompleteImpl, InsMap, ClsMap, I, ExplicitImplProtocols); } else if (ObjCCategoryDecl *C = dyn_cast(CDecl)) { // For extended class, unimplemented methods in its protocols will // be reported in the primary class. if (!C->IsClassExtension()) { for (auto *P : C->protocols()) CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), P, IncompleteImpl, InsMap, ClsMap, CDecl, ExplicitImplProtocols); DiagnoseUnimplementedProperties(S, IMPDecl, CDecl, /*SynthesizeProperties=*/false); } } else llvm_unreachable("invalid ObjCContainerDecl type."); } Sema::DeclGroupPtrTy Sema::ActOnForwardClassDeclaration(SourceLocation AtClassLoc, IdentifierInfo **IdentList, SourceLocation *IdentLocs, ArrayRef TypeParamLists, unsigned NumElts) { SmallVector DeclsInGroup; for (unsigned i = 0; i != NumElts; ++i) { // Check for another declaration kind with the same name. NamedDecl *PrevDecl = LookupSingleName(TUScope, IdentList[i], IdentLocs[i], LookupOrdinaryName, ForRedeclaration); if (PrevDecl && !isa(PrevDecl)) { // GCC apparently allows the following idiom: // // typedef NSObject < XCElementTogglerP > XCElementToggler; // @class XCElementToggler; // // Here we have chosen to ignore the forward class declaration // with a warning. Since this is the implied behavior. TypedefNameDecl *TDD = dyn_cast(PrevDecl); if (!TDD || !TDD->getUnderlyingType()->isObjCObjectType()) { Diag(AtClassLoc, diag::err_redefinition_different_kind) << IdentList[i]; Diag(PrevDecl->getLocation(), diag::note_previous_definition); } else { // a forward class declaration matching a typedef name of a class refers // to the underlying class. Just ignore the forward class with a warning // as this will force the intended behavior which is to lookup the // typedef name. if (isa(TDD->getUnderlyingType())) { Diag(AtClassLoc, diag::warn_forward_class_redefinition) << IdentList[i]; Diag(PrevDecl->getLocation(), diag::note_previous_definition); continue; } } } // Create a declaration to describe this forward declaration. ObjCInterfaceDecl *PrevIDecl = dyn_cast_or_null(PrevDecl); IdentifierInfo *ClassName = IdentList[i]; if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) { // A previous decl with a different name is because of // @compatibility_alias, for example: // \code // @class NewImage; // @compatibility_alias OldImage NewImage; // \endcode // A lookup for 'OldImage' will return the 'NewImage' decl. // // In such a case use the real declaration name, instead of the alias one, // otherwise we will break IdentifierResolver and redecls-chain invariants. // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl // has been aliased. ClassName = PrevIDecl->getIdentifier(); } // If this forward declaration has type parameters, compare them with the // type parameters of the previous declaration. ObjCTypeParamList *TypeParams = TypeParamLists[i]; if (PrevIDecl && TypeParams) { if (ObjCTypeParamList *PrevTypeParams = PrevIDecl->getTypeParamList()) { // Check for consistency with the previous declaration. if (checkTypeParamListConsistency( *this, PrevTypeParams, TypeParams, TypeParamListContext::ForwardDeclaration)) { TypeParams = nullptr; } } else if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) { // The @interface does not have type parameters. Complain. Diag(IdentLocs[i], diag::err_objc_parameterized_forward_class) << ClassName << TypeParams->getSourceRange(); Diag(Def->getLocation(), diag::note_defined_here) << ClassName; TypeParams = nullptr; } } ObjCInterfaceDecl *IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtClassLoc, ClassName, TypeParams, PrevIDecl, IdentLocs[i]); IDecl->setAtEndRange(IdentLocs[i]); PushOnScopeChains(IDecl, TUScope); CheckObjCDeclScope(IDecl); DeclsInGroup.push_back(IDecl); } return BuildDeclaratorGroup(DeclsInGroup, false); } static bool tryMatchRecordTypes(ASTContext &Context, Sema::MethodMatchStrategy strategy, const Type *left, const Type *right); static bool matchTypes(ASTContext &Context, Sema::MethodMatchStrategy strategy, QualType leftQT, QualType rightQT) { const Type *left = Context.getCanonicalType(leftQT).getUnqualifiedType().getTypePtr(); const Type *right = Context.getCanonicalType(rightQT).getUnqualifiedType().getTypePtr(); if (left == right) return true; // If we're doing a strict match, the types have to match exactly. if (strategy == Sema::MMS_strict) return false; if (left->isIncompleteType() || right->isIncompleteType()) return false; // Otherwise, use this absurdly complicated algorithm to try to // validate the basic, low-level compatibility of the two types. // As a minimum, require the sizes and alignments to match. TypeInfo LeftTI = Context.getTypeInfo(left); TypeInfo RightTI = Context.getTypeInfo(right); if (LeftTI.Width != RightTI.Width) return false; if (LeftTI.Align != RightTI.Align) return false; // Consider all the kinds of non-dependent canonical types: // - functions and arrays aren't possible as return and parameter types // - vector types of equal size can be arbitrarily mixed if (isa(left)) return isa(right); if (isa(right)) return false; // - references should only match references of identical type // - structs, unions, and Objective-C objects must match more-or-less // exactly // - everything else should be a scalar if (!left->isScalarType() || !right->isScalarType()) return tryMatchRecordTypes(Context, strategy, left, right); // Make scalars agree in kind, except count bools as chars, and group // all non-member pointers together. Type::ScalarTypeKind leftSK = left->getScalarTypeKind(); Type::ScalarTypeKind rightSK = right->getScalarTypeKind(); if (leftSK == Type::STK_Bool) leftSK = Type::STK_Integral; if (rightSK == Type::STK_Bool) rightSK = Type::STK_Integral; if (leftSK == Type::STK_CPointer || leftSK == Type::STK_BlockPointer) leftSK = Type::STK_ObjCObjectPointer; if (rightSK == Type::STK_CPointer || rightSK == Type::STK_BlockPointer) rightSK = Type::STK_ObjCObjectPointer; // Note that data member pointers and function member pointers don't // intermix because of the size differences. return (leftSK == rightSK); } static bool tryMatchRecordTypes(ASTContext &Context, Sema::MethodMatchStrategy strategy, const Type *lt, const Type *rt) { assert(lt && rt && lt != rt); if (!isa(lt) || !isa(rt)) return false; RecordDecl *left = cast(lt)->getDecl(); RecordDecl *right = cast(rt)->getDecl(); // Require union-hood to match. if (left->isUnion() != right->isUnion()) return false; // Require an exact match if either is non-POD. if ((isa(left) && !cast(left)->isPOD()) || (isa(right) && !cast(right)->isPOD())) return false; // Require size and alignment to match. TypeInfo LeftTI = Context.getTypeInfo(lt); TypeInfo RightTI = Context.getTypeInfo(rt); if (LeftTI.Width != RightTI.Width) return false; if (LeftTI.Align != RightTI.Align) return false; // Require fields to match. RecordDecl::field_iterator li = left->field_begin(), le = left->field_end(); RecordDecl::field_iterator ri = right->field_begin(), re = right->field_end(); for (; li != le && ri != re; ++li, ++ri) { if (!matchTypes(Context, strategy, li->getType(), ri->getType())) return false; } return (li == le && ri == re); } /// MatchTwoMethodDeclarations - Checks that two methods have matching type and /// returns true, or false, accordingly. /// TODO: Handle protocol list; such as id in type comparisons bool Sema::MatchTwoMethodDeclarations(const ObjCMethodDecl *left, const ObjCMethodDecl *right, MethodMatchStrategy strategy) { if (!matchTypes(Context, strategy, left->getReturnType(), right->getReturnType())) return false; // If either is hidden, it is not considered to match. if (left->isHidden() || right->isHidden()) return false; if (getLangOpts().ObjCAutoRefCount && (left->hasAttr() != right->hasAttr() || left->hasAttr() != right->hasAttr())) return false; ObjCMethodDecl::param_const_iterator li = left->param_begin(), le = left->param_end(), ri = right->param_begin(), re = right->param_end(); for (; li != le && ri != re; ++li, ++ri) { assert(ri != right->param_end() && "Param mismatch"); const ParmVarDecl *lparm = *li, *rparm = *ri; if (!matchTypes(Context, strategy, lparm->getType(), rparm->getType())) return false; if (getLangOpts().ObjCAutoRefCount && lparm->hasAttr() != rparm->hasAttr()) return false; } return true; } static bool isMethodContextSameForKindofLookup(ObjCMethodDecl *Method, ObjCMethodDecl *MethodInList) { auto *MethodProtocol = dyn_cast(Method->getDeclContext()); auto *MethodInListProtocol = dyn_cast(MethodInList->getDeclContext()); // If this method belongs to a protocol but the method in list does not, or // vice versa, we say the context is not the same. if ((MethodProtocol && !MethodInListProtocol) || (!MethodProtocol && MethodInListProtocol)) return false; if (MethodProtocol && MethodInListProtocol) return true; ObjCInterfaceDecl *MethodInterface = Method->getClassInterface(); ObjCInterfaceDecl *MethodInListInterface = MethodInList->getClassInterface(); return MethodInterface == MethodInListInterface; } void Sema::addMethodToGlobalList(ObjCMethodList *List, ObjCMethodDecl *Method) { // Record at the head of the list whether there were 0, 1, or >= 2 methods // inside categories. if (ObjCCategoryDecl *CD = dyn_cast(Method->getDeclContext())) if (!CD->IsClassExtension() && List->getBits() < 2) List->setBits(List->getBits() + 1); // If the list is empty, make it a singleton list. if (List->getMethod() == nullptr) { List->setMethod(Method); List->setNext(nullptr); return; } // We've seen a method with this name, see if we have already seen this type // signature. ObjCMethodList *Previous = List; ObjCMethodList *ListWithSameDeclaration = nullptr; for (; List; Previous = List, List = List->getNext()) { // If we are building a module, keep all of the methods. if (getLangOpts().CompilingModule) continue; bool SameDeclaration = MatchTwoMethodDeclarations(Method, List->getMethod()); // Looking for method with a type bound requires the correct context exists. // We need to insert a method into the list if the context is different. // If the method's declaration matches the list // a> the method belongs to a different context: we need to insert it, in // order to emit the availability message, we need to prioritize over // availability among the methods with the same declaration. // b> the method belongs to the same context: there is no need to insert a // new entry. // If the method's declaration does not match the list, we insert it to the // end. if (!SameDeclaration || !isMethodContextSameForKindofLookup(Method, List->getMethod())) { // Even if two method types do not match, we would like to say // there is more than one declaration so unavailability/deprecated // warning is not too noisy. if (!Method->isDefined()) List->setHasMoreThanOneDecl(true); // For methods with the same declaration, the one that is deprecated // should be put in the front for better diagnostics. if (Method->isDeprecated() && SameDeclaration && !ListWithSameDeclaration && !List->getMethod()->isDeprecated()) ListWithSameDeclaration = List; if (Method->isUnavailable() && SameDeclaration && !ListWithSameDeclaration && List->getMethod()->getAvailability() < AR_Deprecated) ListWithSameDeclaration = List; continue; } ObjCMethodDecl *PrevObjCMethod = List->getMethod(); // Propagate the 'defined' bit. if (Method->isDefined()) PrevObjCMethod->setDefined(true); else { // Objective-C doesn't allow an @interface for a class after its // @implementation. So if Method is not defined and there already is // an entry for this type signature, Method has to be for a different // class than PrevObjCMethod. List->setHasMoreThanOneDecl(true); } // If a method is deprecated, push it in the global pool. // This is used for better diagnostics. if (Method->isDeprecated()) { if (!PrevObjCMethod->isDeprecated()) List->setMethod(Method); } // If the new method is unavailable, push it into global pool // unless previous one is deprecated. if (Method->isUnavailable()) { if (PrevObjCMethod->getAvailability() < AR_Deprecated) List->setMethod(Method); } return; } // We have a new signature for an existing method - add it. // This is extremely rare. Only 1% of Cocoa selectors are "overloaded". ObjCMethodList *Mem = BumpAlloc.Allocate(); // We insert it right before ListWithSameDeclaration. if (ListWithSameDeclaration) { auto *List = new (Mem) ObjCMethodList(*ListWithSameDeclaration); // FIXME: should we clear the other bits in ListWithSameDeclaration? ListWithSameDeclaration->setMethod(Method); ListWithSameDeclaration->setNext(List); return; } Previous->setNext(new (Mem) ObjCMethodList(Method)); } /// \brief Read the contents of the method pool for a given selector from /// external storage. void Sema::ReadMethodPool(Selector Sel) { assert(ExternalSource && "We need an external AST source"); ExternalSource->ReadMethodPool(Sel); } void Sema::updateOutOfDateSelector(Selector Sel) { if (!ExternalSource) return; ExternalSource->updateOutOfDateSelector(Sel); } void Sema::AddMethodToGlobalPool(ObjCMethodDecl *Method, bool impl, bool instance) { // Ignore methods of invalid containers. if (cast(Method->getDeclContext())->isInvalidDecl()) return; if (ExternalSource) ReadMethodPool(Method->getSelector()); GlobalMethodPool::iterator Pos = MethodPool.find(Method->getSelector()); if (Pos == MethodPool.end()) Pos = MethodPool.insert(std::make_pair(Method->getSelector(), GlobalMethods())).first; Method->setDefined(impl); ObjCMethodList &Entry = instance ? Pos->second.first : Pos->second.second; addMethodToGlobalList(&Entry, Method); } /// Determines if this is an "acceptable" loose mismatch in the global /// method pool. This exists mostly as a hack to get around certain /// global mismatches which we can't afford to make warnings / errors. /// Really, what we want is a way to take a method out of the global /// method pool. static bool isAcceptableMethodMismatch(ObjCMethodDecl *chosen, ObjCMethodDecl *other) { if (!chosen->isInstanceMethod()) return false; Selector sel = chosen->getSelector(); if (!sel.isUnarySelector() || sel.getNameForSlot(0) != "length") return false; // Don't complain about mismatches for -length if the method we // chose has an integral result type. return (chosen->getReturnType()->isIntegerType()); } /// Return true if the given method is wthin the type bound. static bool FilterMethodsByTypeBound(ObjCMethodDecl *Method, const ObjCObjectType *TypeBound) { if (!TypeBound) return true; if (TypeBound->isObjCId()) // FIXME: should we handle the case of bounding to id differently? return true; auto *BoundInterface = TypeBound->getInterface(); assert(BoundInterface && "unexpected object type!"); // Check if the Method belongs to a protocol. We should allow any method // defined in any protocol, because any subclass could adopt the protocol. auto *MethodProtocol = dyn_cast(Method->getDeclContext()); if (MethodProtocol) { return true; } // If the Method belongs to a class, check if it belongs to the class // hierarchy of the class bound. if (ObjCInterfaceDecl *MethodInterface = Method->getClassInterface()) { // We allow methods declared within classes that are part of the hierarchy // of the class bound (superclass of, subclass of, or the same as the class // bound). return MethodInterface == BoundInterface || MethodInterface->isSuperClassOf(BoundInterface) || BoundInterface->isSuperClassOf(MethodInterface); } llvm_unreachable("unknow method context"); } /// We first select the type of the method: Instance or Factory, then collect /// all methods with that type. bool Sema::CollectMultipleMethodsInGlobalPool( Selector Sel, SmallVectorImpl &Methods, bool InstanceFirst, bool CheckTheOther, const ObjCObjectType *TypeBound) { if (ExternalSource) ReadMethodPool(Sel); GlobalMethodPool::iterator Pos = MethodPool.find(Sel); if (Pos == MethodPool.end()) return false; // Gather the non-hidden methods. ObjCMethodList &MethList = InstanceFirst ? Pos->second.first : Pos->second.second; for (ObjCMethodList *M = &MethList; M; M = M->getNext()) if (M->getMethod() && !M->getMethod()->isHidden()) { if (FilterMethodsByTypeBound(M->getMethod(), TypeBound)) Methods.push_back(M->getMethod()); } // Return if we find any method with the desired kind. if (!Methods.empty()) return Methods.size() > 1; if (!CheckTheOther) return false; // Gather the other kind. ObjCMethodList &MethList2 = InstanceFirst ? Pos->second.second : Pos->second.first; for (ObjCMethodList *M = &MethList2; M; M = M->getNext()) if (M->getMethod() && !M->getMethod()->isHidden()) { if (FilterMethodsByTypeBound(M->getMethod(), TypeBound)) Methods.push_back(M->getMethod()); } return Methods.size() > 1; } bool Sema::AreMultipleMethodsInGlobalPool( Selector Sel, ObjCMethodDecl *BestMethod, SourceRange R, bool receiverIdOrClass, SmallVectorImpl &Methods) { // Diagnose finding more than one method in global pool. SmallVector FilteredMethods; FilteredMethods.push_back(BestMethod); for (auto *M : Methods) if (M != BestMethod && !M->hasAttr()) FilteredMethods.push_back(M); if (FilteredMethods.size() > 1) DiagnoseMultipleMethodInGlobalPool(FilteredMethods, Sel, R, receiverIdOrClass); GlobalMethodPool::iterator Pos = MethodPool.find(Sel); // Test for no method in the pool which should not trigger any warning by // caller. if (Pos == MethodPool.end()) return true; ObjCMethodList &MethList = BestMethod->isInstanceMethod() ? Pos->second.first : Pos->second.second; return MethList.hasMoreThanOneDecl(); } ObjCMethodDecl *Sema::LookupMethodInGlobalPool(Selector Sel, SourceRange R, bool receiverIdOrClass, bool instance) { if (ExternalSource) ReadMethodPool(Sel); GlobalMethodPool::iterator Pos = MethodPool.find(Sel); if (Pos == MethodPool.end()) return nullptr; // Gather the non-hidden methods. ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second; SmallVector Methods; for (ObjCMethodList *M = &MethList; M; M = M->getNext()) { if (M->getMethod() && !M->getMethod()->isHidden()) return M->getMethod(); } return nullptr; } void Sema::DiagnoseMultipleMethodInGlobalPool(SmallVectorImpl &Methods, Selector Sel, SourceRange R, bool receiverIdOrClass) { // We found multiple methods, so we may have to complain. bool issueDiagnostic = false, issueError = false; // We support a warning which complains about *any* difference in // method signature. bool strictSelectorMatch = receiverIdOrClass && !Diags.isIgnored(diag::warn_strict_multiple_method_decl, R.getBegin()); if (strictSelectorMatch) { for (unsigned I = 1, N = Methods.size(); I != N; ++I) { if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_strict)) { issueDiagnostic = true; break; } } } // If we didn't see any strict differences, we won't see any loose // differences. In ARC, however, we also need to check for loose // mismatches, because most of them are errors. if (!strictSelectorMatch || (issueDiagnostic && getLangOpts().ObjCAutoRefCount)) for (unsigned I = 1, N = Methods.size(); I != N; ++I) { // This checks if the methods differ in type mismatch. if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_loose) && !isAcceptableMethodMismatch(Methods[0], Methods[I])) { issueDiagnostic = true; if (getLangOpts().ObjCAutoRefCount) issueError = true; break; } } if (issueDiagnostic) { if (issueError) Diag(R.getBegin(), diag::err_arc_multiple_method_decl) << Sel << R; else if (strictSelectorMatch) Diag(R.getBegin(), diag::warn_strict_multiple_method_decl) << Sel << R; else Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R; Diag(Methods[0]->getLocStart(), issueError ? diag::note_possibility : diag::note_using) << Methods[0]->getSourceRange(); for (unsigned I = 1, N = Methods.size(); I != N; ++I) { Diag(Methods[I]->getLocStart(), diag::note_also_found) << Methods[I]->getSourceRange(); } } } ObjCMethodDecl *Sema::LookupImplementedMethodInGlobalPool(Selector Sel) { GlobalMethodPool::iterator Pos = MethodPool.find(Sel); if (Pos == MethodPool.end()) return nullptr; GlobalMethods &Methods = Pos->second; for (const ObjCMethodList *Method = &Methods.first; Method; Method = Method->getNext()) if (Method->getMethod() && (Method->getMethod()->isDefined() || Method->getMethod()->isPropertyAccessor())) return Method->getMethod(); for (const ObjCMethodList *Method = &Methods.second; Method; Method = Method->getNext()) if (Method->getMethod() && (Method->getMethod()->isDefined() || Method->getMethod()->isPropertyAccessor())) return Method->getMethod(); return nullptr; } static void HelperSelectorsForTypoCorrection( SmallVectorImpl &BestMethod, StringRef Typo, const ObjCMethodDecl * Method) { const unsigned MaxEditDistance = 1; unsigned BestEditDistance = MaxEditDistance + 1; std::string MethodName = Method->getSelector().getAsString(); unsigned MinPossibleEditDistance = abs((int)MethodName.size() - (int)Typo.size()); if (MinPossibleEditDistance > 0 && Typo.size() / MinPossibleEditDistance < 1) return; unsigned EditDistance = Typo.edit_distance(MethodName, true, MaxEditDistance); if (EditDistance > MaxEditDistance) return; if (EditDistance == BestEditDistance) BestMethod.push_back(Method); else if (EditDistance < BestEditDistance) { BestMethod.clear(); BestMethod.push_back(Method); } } static bool HelperIsMethodInObjCType(Sema &S, Selector Sel, QualType ObjectType) { if (ObjectType.isNull()) return true; if (S.LookupMethodInObjectType(Sel, ObjectType, true/*Instance method*/)) return true; return S.LookupMethodInObjectType(Sel, ObjectType, false/*Class method*/) != nullptr; } const ObjCMethodDecl * Sema::SelectorsForTypoCorrection(Selector Sel, QualType ObjectType) { unsigned NumArgs = Sel.getNumArgs(); SmallVector Methods; bool ObjectIsId = true, ObjectIsClass = true; if (ObjectType.isNull()) ObjectIsId = ObjectIsClass = false; else if (!ObjectType->isObjCObjectPointerType()) return nullptr; else if (const ObjCObjectPointerType *ObjCPtr = ObjectType->getAsObjCInterfacePointerType()) { ObjectType = QualType(ObjCPtr->getInterfaceType(), 0); ObjectIsId = ObjectIsClass = false; } else if (ObjectType->isObjCIdType() || ObjectType->isObjCQualifiedIdType()) ObjectIsClass = false; else if (ObjectType->isObjCClassType() || ObjectType->isObjCQualifiedClassType()) ObjectIsId = false; else return nullptr; for (GlobalMethodPool::iterator b = MethodPool.begin(), e = MethodPool.end(); b != e; b++) { // instance methods for (ObjCMethodList *M = &b->second.first; M; M=M->getNext()) if (M->getMethod() && (M->getMethod()->getSelector().getNumArgs() == NumArgs) && (M->getMethod()->getSelector() != Sel)) { if (ObjectIsId) Methods.push_back(M->getMethod()); else if (!ObjectIsClass && HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(), ObjectType)) Methods.push_back(M->getMethod()); } // class methods for (ObjCMethodList *M = &b->second.second; M; M=M->getNext()) if (M->getMethod() && (M->getMethod()->getSelector().getNumArgs() == NumArgs) && (M->getMethod()->getSelector() != Sel)) { if (ObjectIsClass) Methods.push_back(M->getMethod()); else if (!ObjectIsId && HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(), ObjectType)) Methods.push_back(M->getMethod()); } } SmallVector SelectedMethods; for (unsigned i = 0, e = Methods.size(); i < e; i++) { HelperSelectorsForTypoCorrection(SelectedMethods, Sel.getAsString(), Methods[i]); } return (SelectedMethods.size() == 1) ? SelectedMethods[0] : nullptr; } /// DiagnoseDuplicateIvars - /// Check for duplicate ivars in the entire class at the start of /// \@implementation. This becomes necesssary because class extension can /// add ivars to a class in random order which will not be known until /// class's \@implementation is seen. void Sema::DiagnoseDuplicateIvars(ObjCInterfaceDecl *ID, ObjCInterfaceDecl *SID) { for (auto *Ivar : ID->ivars()) { if (Ivar->isInvalidDecl()) continue; if (IdentifierInfo *II = Ivar->getIdentifier()) { ObjCIvarDecl* prevIvar = SID->lookupInstanceVariable(II); if (prevIvar) { Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; Diag(prevIvar->getLocation(), diag::note_previous_declaration); Ivar->setInvalidDecl(); } } } } /// Diagnose attempts to define ARC-__weak ivars when __weak is disabled. static void DiagnoseWeakIvars(Sema &S, ObjCImplementationDecl *ID) { if (S.getLangOpts().ObjCWeak) return; for (auto ivar = ID->getClassInterface()->all_declared_ivar_begin(); ivar; ivar = ivar->getNextIvar()) { if (ivar->isInvalidDecl()) continue; if (ivar->getType().getObjCLifetime() == Qualifiers::OCL_Weak) { if (S.getLangOpts().ObjCWeakRuntime) { S.Diag(ivar->getLocation(), diag::err_arc_weak_disabled); } else { S.Diag(ivar->getLocation(), diag::err_arc_weak_no_runtime); } } } } Sema::ObjCContainerKind Sema::getObjCContainerKind() const { switch (CurContext->getDeclKind()) { case Decl::ObjCInterface: return Sema::OCK_Interface; case Decl::ObjCProtocol: return Sema::OCK_Protocol; case Decl::ObjCCategory: if (cast(CurContext)->IsClassExtension()) return Sema::OCK_ClassExtension; return Sema::OCK_Category; case Decl::ObjCImplementation: return Sema::OCK_Implementation; case Decl::ObjCCategoryImpl: return Sema::OCK_CategoryImplementation; default: return Sema::OCK_None; } } // Note: For class/category implementations, allMethods is always null. Decl *Sema::ActOnAtEnd(Scope *S, SourceRange AtEnd, ArrayRef allMethods, ArrayRef allTUVars) { if (getObjCContainerKind() == Sema::OCK_None) return nullptr; assert(AtEnd.isValid() && "Invalid location for '@end'"); ObjCContainerDecl *OCD = dyn_cast(CurContext); Decl *ClassDecl = cast(OCD); bool isInterfaceDeclKind = isa(ClassDecl) || isa(ClassDecl) || isa(ClassDecl); bool checkIdenticalMethods = isa(ClassDecl); // FIXME: Remove these and use the ObjCContainerDecl/DeclContext. llvm::DenseMap InsMap; llvm::DenseMap ClsMap; for (unsigned i = 0, e = allMethods.size(); i != e; i++ ) { ObjCMethodDecl *Method = cast_or_null(allMethods[i]); if (!Method) continue; // Already issued a diagnostic. if (Method->isInstanceMethod()) { /// Check for instance method of the same name with incompatible types const ObjCMethodDecl *&PrevMethod = InsMap[Method->getSelector()]; bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod) : false; if ((isInterfaceDeclKind && PrevMethod && !match) || (checkIdenticalMethods && match)) { Diag(Method->getLocation(), diag::err_duplicate_method_decl) << Method->getDeclName(); Diag(PrevMethod->getLocation(), diag::note_previous_declaration); Method->setInvalidDecl(); } else { if (PrevMethod) { Method->setAsRedeclaration(PrevMethod); if (!Context.getSourceManager().isInSystemHeader( Method->getLocation())) Diag(Method->getLocation(), diag::warn_duplicate_method_decl) << Method->getDeclName(); Diag(PrevMethod->getLocation(), diag::note_previous_declaration); } InsMap[Method->getSelector()] = Method; /// The following allows us to typecheck messages to "id". AddInstanceMethodToGlobalPool(Method); } } else { /// Check for class method of the same name with incompatible types const ObjCMethodDecl *&PrevMethod = ClsMap[Method->getSelector()]; bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod) : false; if ((isInterfaceDeclKind && PrevMethod && !match) || (checkIdenticalMethods && match)) { Diag(Method->getLocation(), diag::err_duplicate_method_decl) << Method->getDeclName(); Diag(PrevMethod->getLocation(), diag::note_previous_declaration); Method->setInvalidDecl(); } else { if (PrevMethod) { Method->setAsRedeclaration(PrevMethod); if (!Context.getSourceManager().isInSystemHeader( Method->getLocation())) Diag(Method->getLocation(), diag::warn_duplicate_method_decl) << Method->getDeclName(); Diag(PrevMethod->getLocation(), diag::note_previous_declaration); } ClsMap[Method->getSelector()] = Method; AddFactoryMethodToGlobalPool(Method); } } } if (isa(ClassDecl)) { // Nothing to do here. } else if (ObjCCategoryDecl *C = dyn_cast(ClassDecl)) { // Categories are used to extend the class by declaring new methods. // By the same token, they are also used to add new properties. No // need to compare the added property to those in the class. if (C->IsClassExtension()) { ObjCInterfaceDecl *CCPrimary = C->getClassInterface(); DiagnoseClassExtensionDupMethods(C, CCPrimary); } } if (ObjCContainerDecl *CDecl = dyn_cast(ClassDecl)) { if (CDecl->getIdentifier()) // ProcessPropertyDecl is responsible for diagnosing conflicts with any // user-defined setter/getter. It also synthesizes setter/getter methods // and adds them to the DeclContext and global method pools. for (auto *I : CDecl->properties()) ProcessPropertyDecl(I); CDecl->setAtEndRange(AtEnd); } if (ObjCImplementationDecl *IC=dyn_cast(ClassDecl)) { IC->setAtEndRange(AtEnd); if (ObjCInterfaceDecl* IDecl = IC->getClassInterface()) { // Any property declared in a class extension might have user // declared setter or getter in current class extension or one // of the other class extensions. Mark them as synthesized as // property will be synthesized when property with same name is // seen in the @implementation. for (const auto *Ext : IDecl->visible_extensions()) { for (const auto *Property : Ext->instance_properties()) { // Skip over properties declared @dynamic if (const ObjCPropertyImplDecl *PIDecl = IC->FindPropertyImplDecl(Property->getIdentifier(), Property->getQueryKind())) if (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic) continue; for (const auto *Ext : IDecl->visible_extensions()) { if (ObjCMethodDecl *GetterMethod = Ext->getInstanceMethod(Property->getGetterName())) GetterMethod->setPropertyAccessor(true); if (!Property->isReadOnly()) if (ObjCMethodDecl *SetterMethod = Ext->getInstanceMethod(Property->getSetterName())) SetterMethod->setPropertyAccessor(true); } } } ImplMethodsVsClassMethods(S, IC, IDecl); AtomicPropertySetterGetterRules(IC, IDecl); DiagnoseOwningPropertyGetterSynthesis(IC); DiagnoseUnusedBackingIvarInAccessor(S, IC); if (IDecl->hasDesignatedInitializers()) DiagnoseMissingDesignatedInitOverrides(IC, IDecl); DiagnoseWeakIvars(*this, IC); bool HasRootClassAttr = IDecl->hasAttr(); if (IDecl->getSuperClass() == nullptr) { // This class has no superclass, so check that it has been marked with // __attribute((objc_root_class)). if (!HasRootClassAttr) { SourceLocation DeclLoc(IDecl->getLocation()); SourceLocation SuperClassLoc(getLocForEndOfToken(DeclLoc)); Diag(DeclLoc, diag::warn_objc_root_class_missing) << IDecl->getIdentifier(); // See if NSObject is in the current scope, and if it is, suggest // adding " : NSObject " to the class declaration. NamedDecl *IF = LookupSingleName(TUScope, NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject), DeclLoc, LookupOrdinaryName); ObjCInterfaceDecl *NSObjectDecl = dyn_cast_or_null(IF); if (NSObjectDecl && NSObjectDecl->getDefinition()) { Diag(SuperClassLoc, diag::note_objc_needs_superclass) << FixItHint::CreateInsertion(SuperClassLoc, " : NSObject "); } else { Diag(SuperClassLoc, diag::note_objc_needs_superclass); } } } else if (HasRootClassAttr) { // Complain that only root classes may have this attribute. Diag(IDecl->getLocation(), diag::err_objc_root_class_subclass); } if (LangOpts.ObjCRuntime.isNonFragile()) { while (IDecl->getSuperClass()) { DiagnoseDuplicateIvars(IDecl, IDecl->getSuperClass()); IDecl = IDecl->getSuperClass(); } } } SetIvarInitializers(IC); } else if (ObjCCategoryImplDecl* CatImplClass = dyn_cast(ClassDecl)) { CatImplClass->setAtEndRange(AtEnd); // Find category interface decl and then check that all methods declared // in this interface are implemented in the category @implementation. if (ObjCInterfaceDecl* IDecl = CatImplClass->getClassInterface()) { if (ObjCCategoryDecl *Cat = IDecl->FindCategoryDeclaration(CatImplClass->getIdentifier())) { ImplMethodsVsClassMethods(S, CatImplClass, Cat); } } } if (isInterfaceDeclKind) { // Reject invalid vardecls. for (unsigned i = 0, e = allTUVars.size(); i != e; i++) { DeclGroupRef DG = allTUVars[i].get(); for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) if (VarDecl *VDecl = dyn_cast(*I)) { if (!VDecl->hasExternalStorage()) Diag(VDecl->getLocation(), diag::err_objc_var_decl_inclass); } } } ActOnObjCContainerFinishDefinition(); for (unsigned i = 0, e = allTUVars.size(); i != e; i++) { DeclGroupRef DG = allTUVars[i].get(); for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) (*I)->setTopLevelDeclInObjCContainer(); Consumer.HandleTopLevelDeclInObjCContainer(DG); } ActOnDocumentableDecl(ClassDecl); return ClassDecl; } /// CvtQTToAstBitMask - utility routine to produce an AST bitmask for /// objective-c's type qualifier from the parser version of the same info. static Decl::ObjCDeclQualifier CvtQTToAstBitMask(ObjCDeclSpec::ObjCDeclQualifier PQTVal) { return (Decl::ObjCDeclQualifier) (unsigned) PQTVal; } /// \brief Check whether the declared result type of the given Objective-C /// method declaration is compatible with the method's class. /// static Sema::ResultTypeCompatibilityKind CheckRelatedResultTypeCompatibility(Sema &S, ObjCMethodDecl *Method, ObjCInterfaceDecl *CurrentClass) { QualType ResultType = Method->getReturnType(); // If an Objective-C method inherits its related result type, then its // declared result type must be compatible with its own class type. The // declared result type is compatible if: if (const ObjCObjectPointerType *ResultObjectType = ResultType->getAs()) { // - it is id or qualified id, or if (ResultObjectType->isObjCIdType() || ResultObjectType->isObjCQualifiedIdType()) return Sema::RTC_Compatible; if (CurrentClass) { if (ObjCInterfaceDecl *ResultClass = ResultObjectType->getInterfaceDecl()) { // - it is the same as the method's class type, or if (declaresSameEntity(CurrentClass, ResultClass)) return Sema::RTC_Compatible; // - it is a superclass of the method's class type if (ResultClass->isSuperClassOf(CurrentClass)) return Sema::RTC_Compatible; } } else { // Any Objective-C pointer type might be acceptable for a protocol // method; we just don't know. return Sema::RTC_Unknown; } } return Sema::RTC_Incompatible; } namespace { /// A helper class for searching for methods which a particular method /// overrides. class OverrideSearch { public: Sema &S; ObjCMethodDecl *Method; llvm::SmallPtrSet Overridden; bool Recursive; public: OverrideSearch(Sema &S, ObjCMethodDecl *method) : S(S), Method(method) { Selector selector = method->getSelector(); // Bypass this search if we've never seen an instance/class method // with this selector before. Sema::GlobalMethodPool::iterator it = S.MethodPool.find(selector); if (it == S.MethodPool.end()) { if (!S.getExternalSource()) return; S.ReadMethodPool(selector); it = S.MethodPool.find(selector); if (it == S.MethodPool.end()) return; } ObjCMethodList &list = method->isInstanceMethod() ? it->second.first : it->second.second; if (!list.getMethod()) return; ObjCContainerDecl *container = cast(method->getDeclContext()); // Prevent the search from reaching this container again. This is // important with categories, which override methods from the // interface and each other. if (ObjCCategoryDecl *Category = dyn_cast(container)) { searchFromContainer(container); if (ObjCInterfaceDecl *Interface = Category->getClassInterface()) searchFromContainer(Interface); } else { searchFromContainer(container); } } typedef llvm::SmallPtrSetImpl::iterator iterator; iterator begin() const { return Overridden.begin(); } iterator end() const { return Overridden.end(); } private: void searchFromContainer(ObjCContainerDecl *container) { if (container->isInvalidDecl()) return; switch (container->getDeclKind()) { #define OBJCCONTAINER(type, base) \ case Decl::type: \ searchFrom(cast(container)); \ break; #define ABSTRACT_DECL(expansion) #define DECL(type, base) \ case Decl::type: #include "clang/AST/DeclNodes.inc" llvm_unreachable("not an ObjC container!"); } } void searchFrom(ObjCProtocolDecl *protocol) { if (!protocol->hasDefinition()) return; // A method in a protocol declaration overrides declarations from // referenced ("parent") protocols. search(protocol->getReferencedProtocols()); } void searchFrom(ObjCCategoryDecl *category) { // A method in a category declaration overrides declarations from // the main class and from protocols the category references. // The main class is handled in the constructor. search(category->getReferencedProtocols()); } void searchFrom(ObjCCategoryImplDecl *impl) { // A method in a category definition that has a category // declaration overrides declarations from the category // declaration. if (ObjCCategoryDecl *category = impl->getCategoryDecl()) { search(category); if (ObjCInterfaceDecl *Interface = category->getClassInterface()) search(Interface); // Otherwise it overrides declarations from the class. } else if (ObjCInterfaceDecl *Interface = impl->getClassInterface()) { search(Interface); } } void searchFrom(ObjCInterfaceDecl *iface) { // A method in a class declaration overrides declarations from if (!iface->hasDefinition()) return; // - categories, for (auto *Cat : iface->known_categories()) search(Cat); // - the super class, and if (ObjCInterfaceDecl *super = iface->getSuperClass()) search(super); // - any referenced protocols. search(iface->getReferencedProtocols()); } void searchFrom(ObjCImplementationDecl *impl) { // A method in a class implementation overrides declarations from // the class interface. if (ObjCInterfaceDecl *Interface = impl->getClassInterface()) search(Interface); } void search(const ObjCProtocolList &protocols) { for (ObjCProtocolList::iterator i = protocols.begin(), e = protocols.end(); i != e; ++i) search(*i); } void search(ObjCContainerDecl *container) { // Check for a method in this container which matches this selector. ObjCMethodDecl *meth = container->getMethod(Method->getSelector(), Method->isInstanceMethod(), /*AllowHidden=*/true); // If we find one, record it and bail out. if (meth) { Overridden.insert(meth); return; } // Otherwise, search for methods that a hypothetical method here // would have overridden. // Note that we're now in a recursive case. Recursive = true; searchFromContainer(container); } }; } // end anonymous namespace void Sema::CheckObjCMethodOverrides(ObjCMethodDecl *ObjCMethod, ObjCInterfaceDecl *CurrentClass, ResultTypeCompatibilityKind RTC) { // Search for overridden methods and merge information down from them. OverrideSearch overrides(*this, ObjCMethod); // Keep track if the method overrides any method in the class's base classes, // its protocols, or its categories' protocols; we will keep that info // in the ObjCMethodDecl. // For this info, a method in an implementation is not considered as // overriding the same method in the interface or its categories. bool hasOverriddenMethodsInBaseOrProtocol = false; for (OverrideSearch::iterator i = overrides.begin(), e = overrides.end(); i != e; ++i) { ObjCMethodDecl *overridden = *i; if (!hasOverriddenMethodsInBaseOrProtocol) { if (isa(overridden->getDeclContext()) || CurrentClass != overridden->getClassInterface() || overridden->isOverriding()) { hasOverriddenMethodsInBaseOrProtocol = true; } else if (isa(ObjCMethod->getDeclContext())) { // OverrideSearch will return as "overridden" the same method in the // interface. For hasOverriddenMethodsInBaseOrProtocol, we need to // check whether a category of a base class introduced a method with the // same selector, after the interface method declaration. // To avoid unnecessary lookups in the majority of cases, we use the // extra info bits in GlobalMethodPool to check whether there were any // category methods with this selector. GlobalMethodPool::iterator It = MethodPool.find(ObjCMethod->getSelector()); if (It != MethodPool.end()) { ObjCMethodList &List = ObjCMethod->isInstanceMethod()? It->second.first: It->second.second; unsigned CategCount = List.getBits(); if (CategCount > 0) { // If the method is in a category we'll do lookup if there were at // least 2 category methods recorded, otherwise only one will do. if (CategCount > 1 || !isa(overridden->getDeclContext())) { OverrideSearch overrides(*this, overridden); for (OverrideSearch::iterator OI= overrides.begin(), OE= overrides.end(); OI!=OE; ++OI) { ObjCMethodDecl *SuperOverridden = *OI; if (isa(SuperOverridden->getDeclContext()) || CurrentClass != SuperOverridden->getClassInterface()) { hasOverriddenMethodsInBaseOrProtocol = true; overridden->setOverriding(true); break; } } } } } } } // Propagate down the 'related result type' bit from overridden methods. if (RTC != Sema::RTC_Incompatible && overridden->hasRelatedResultType()) ObjCMethod->SetRelatedResultType(); // Then merge the declarations. mergeObjCMethodDecls(ObjCMethod, overridden); if (ObjCMethod->isImplicit() && overridden->isImplicit()) continue; // Conflicting properties are detected elsewhere. // Check for overriding methods if (isa(ObjCMethod->getDeclContext()) || isa(ObjCMethod->getDeclContext())) CheckConflictingOverridingMethod(ObjCMethod, overridden, isa(overridden->getDeclContext())); if (CurrentClass && overridden->getDeclContext() != CurrentClass && isa(overridden->getDeclContext()) && !overridden->isImplicit() /* not meant for properties */) { ObjCMethodDecl::param_iterator ParamI = ObjCMethod->param_begin(), E = ObjCMethod->param_end(); ObjCMethodDecl::param_iterator PrevI = overridden->param_begin(), PrevE = overridden->param_end(); for (; ParamI != E && PrevI != PrevE; ++ParamI, ++PrevI) { assert(PrevI != overridden->param_end() && "Param mismatch"); QualType T1 = Context.getCanonicalType((*ParamI)->getType()); QualType T2 = Context.getCanonicalType((*PrevI)->getType()); // If type of argument of method in this class does not match its // respective argument type in the super class method, issue warning; if (!Context.typesAreCompatible(T1, T2)) { Diag((*ParamI)->getLocation(), diag::ext_typecheck_base_super) << T1 << T2; Diag(overridden->getLocation(), diag::note_previous_declaration); break; } } } } ObjCMethod->setOverriding(hasOverriddenMethodsInBaseOrProtocol); } /// Merge type nullability from for a redeclaration of the same entity, /// producing the updated type of the redeclared entity. static QualType mergeTypeNullabilityForRedecl(Sema &S, SourceLocation loc, QualType type, bool usesCSKeyword, SourceLocation prevLoc, QualType prevType, bool prevUsesCSKeyword) { // Determine the nullability of both types. auto nullability = type->getNullability(S.Context); auto prevNullability = prevType->getNullability(S.Context); // Easy case: both have nullability. if (nullability.hasValue() == prevNullability.hasValue()) { // Neither has nullability; continue. if (!nullability) return type; // The nullabilities are equivalent; do nothing. if (*nullability == *prevNullability) return type; // Complain about mismatched nullability. S.Diag(loc, diag::err_nullability_conflicting) << DiagNullabilityKind(*nullability, usesCSKeyword) << DiagNullabilityKind(*prevNullability, prevUsesCSKeyword); return type; } // If it's the redeclaration that has nullability, don't change anything. if (nullability) return type; // Otherwise, provide the result with the same nullability. return S.Context.getAttributedType( AttributedType::getNullabilityAttrKind(*prevNullability), type, type); } /// Merge information from the declaration of a method in the \@interface /// (or a category/extension) into the corresponding method in the /// @implementation (for a class or category). static void mergeInterfaceMethodToImpl(Sema &S, ObjCMethodDecl *method, ObjCMethodDecl *prevMethod) { // Merge the objc_requires_super attribute. if (prevMethod->hasAttr() && !method->hasAttr()) { // merge the attribute into implementation. method->addAttr( ObjCRequiresSuperAttr::CreateImplicit(S.Context, method->getLocation())); } // Merge nullability of the result type. QualType newReturnType = mergeTypeNullabilityForRedecl( S, method->getReturnTypeSourceRange().getBegin(), method->getReturnType(), method->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability, prevMethod->getReturnTypeSourceRange().getBegin(), prevMethod->getReturnType(), prevMethod->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability); method->setReturnType(newReturnType); // Handle each of the parameters. unsigned numParams = method->param_size(); unsigned numPrevParams = prevMethod->param_size(); for (unsigned i = 0, n = std::min(numParams, numPrevParams); i != n; ++i) { ParmVarDecl *param = method->param_begin()[i]; ParmVarDecl *prevParam = prevMethod->param_begin()[i]; // Merge nullability. QualType newParamType = mergeTypeNullabilityForRedecl( S, param->getLocation(), param->getType(), param->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability, prevParam->getLocation(), prevParam->getType(), prevParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability); param->setType(newParamType); } } Decl *Sema::ActOnMethodDeclaration( Scope *S, SourceLocation MethodLoc, SourceLocation EndLoc, tok::TokenKind MethodType, ObjCDeclSpec &ReturnQT, ParsedType ReturnType, ArrayRef SelectorLocs, Selector Sel, // optional arguments. The number of types/arguments is obtained // from the Sel.getNumArgs(). ObjCArgInfo *ArgInfo, DeclaratorChunk::ParamInfo *CParamInfo, unsigned CNumArgs, // c-style args AttributeList *AttrList, tok::ObjCKeywordKind MethodDeclKind, bool isVariadic, bool MethodDefinition) { // Make sure we can establish a context for the method. if (!CurContext->isObjCContainer()) { Diag(MethodLoc, diag::error_missing_method_context); return nullptr; } ObjCContainerDecl *OCD = dyn_cast(CurContext); Decl *ClassDecl = cast(OCD); QualType resultDeclType; bool HasRelatedResultType = false; TypeSourceInfo *ReturnTInfo = nullptr; if (ReturnType) { resultDeclType = GetTypeFromParser(ReturnType, &ReturnTInfo); if (CheckFunctionReturnType(resultDeclType, MethodLoc)) return nullptr; QualType bareResultType = resultDeclType; (void)AttributedType::stripOuterNullability(bareResultType); HasRelatedResultType = (bareResultType == Context.getObjCInstanceType()); } else { // get the type for "id". resultDeclType = Context.getObjCIdType(); Diag(MethodLoc, diag::warn_missing_method_return_type) << FixItHint::CreateInsertion(SelectorLocs.front(), "(id)"); } ObjCMethodDecl *ObjCMethod = ObjCMethodDecl::Create( Context, MethodLoc, EndLoc, Sel, resultDeclType, ReturnTInfo, CurContext, MethodType == tok::minus, isVariadic, /*isPropertyAccessor=*/false, /*isImplicitlyDeclared=*/false, /*isDefined=*/false, MethodDeclKind == tok::objc_optional ? ObjCMethodDecl::Optional : ObjCMethodDecl::Required, HasRelatedResultType); SmallVector Params; for (unsigned i = 0, e = Sel.getNumArgs(); i != e; ++i) { QualType ArgType; TypeSourceInfo *DI; if (!ArgInfo[i].Type) { ArgType = Context.getObjCIdType(); DI = nullptr; } else { ArgType = GetTypeFromParser(ArgInfo[i].Type, &DI); } LookupResult R(*this, ArgInfo[i].Name, ArgInfo[i].NameLoc, LookupOrdinaryName, ForRedeclaration); LookupName(R, S); if (R.isSingleResult()) { NamedDecl *PrevDecl = R.getFoundDecl(); if (S->isDeclScope(PrevDecl)) { Diag(ArgInfo[i].NameLoc, (MethodDefinition ? diag::warn_method_param_redefinition : diag::warn_method_param_declaration)) << ArgInfo[i].Name; Diag(PrevDecl->getLocation(), diag::note_previous_declaration); } } SourceLocation StartLoc = DI ? DI->getTypeLoc().getBeginLoc() : ArgInfo[i].NameLoc; ParmVarDecl* Param = CheckParameter(ObjCMethod, StartLoc, ArgInfo[i].NameLoc, ArgInfo[i].Name, ArgType, DI, SC_None); Param->setObjCMethodScopeInfo(i); Param->setObjCDeclQualifier( CvtQTToAstBitMask(ArgInfo[i].DeclSpec.getObjCDeclQualifier())); // Apply the attributes to the parameter. ProcessDeclAttributeList(TUScope, Param, ArgInfo[i].ArgAttrs); if (Param->hasAttr()) { Diag(Param->getLocation(), diag::err_block_on_nonlocal); Param->setInvalidDecl(); } S->AddDecl(Param); IdResolver.AddDecl(Param); Params.push_back(Param); } for (unsigned i = 0, e = CNumArgs; i != e; ++i) { ParmVarDecl *Param = cast(CParamInfo[i].Param); QualType ArgType = Param->getType(); if (ArgType.isNull()) ArgType = Context.getObjCIdType(); else // Perform the default array/function conversions (C99 6.7.5.3p[7,8]). ArgType = Context.getAdjustedParameterType(ArgType); Param->setDeclContext(ObjCMethod); Params.push_back(Param); } ObjCMethod->setMethodParams(Context, Params, SelectorLocs); ObjCMethod->setObjCDeclQualifier( CvtQTToAstBitMask(ReturnQT.getObjCDeclQualifier())); if (AttrList) ProcessDeclAttributeList(TUScope, ObjCMethod, AttrList); // Add the method now. const ObjCMethodDecl *PrevMethod = nullptr; if (ObjCImplDecl *ImpDecl = dyn_cast(ClassDecl)) { if (MethodType == tok::minus) { PrevMethod = ImpDecl->getInstanceMethod(Sel); ImpDecl->addInstanceMethod(ObjCMethod); } else { PrevMethod = ImpDecl->getClassMethod(Sel); ImpDecl->addClassMethod(ObjCMethod); } // Merge information from the @interface declaration into the // @implementation. if (ObjCInterfaceDecl *IDecl = ImpDecl->getClassInterface()) { if (auto *IMD = IDecl->lookupMethod(ObjCMethod->getSelector(), ObjCMethod->isInstanceMethod())) { mergeInterfaceMethodToImpl(*this, ObjCMethod, IMD); // Warn about defining -dealloc in a category. if (isa(ImpDecl) && IMD->isOverriding() && ObjCMethod->getSelector().getMethodFamily() == OMF_dealloc) { Diag(ObjCMethod->getLocation(), diag::warn_dealloc_in_category) << ObjCMethod->getDeclName(); } } } } else { cast(ClassDecl)->addDecl(ObjCMethod); } if (PrevMethod) { // You can never have two method definitions with the same name. Diag(ObjCMethod->getLocation(), diag::err_duplicate_method_decl) << ObjCMethod->getDeclName(); Diag(PrevMethod->getLocation(), diag::note_previous_declaration); ObjCMethod->setInvalidDecl(); return ObjCMethod; } // If this Objective-C method does not have a related result type, but we // are allowed to infer related result types, try to do so based on the // method family. ObjCInterfaceDecl *CurrentClass = dyn_cast(ClassDecl); if (!CurrentClass) { if (ObjCCategoryDecl *Cat = dyn_cast(ClassDecl)) CurrentClass = Cat->getClassInterface(); else if (ObjCImplDecl *Impl = dyn_cast(ClassDecl)) CurrentClass = Impl->getClassInterface(); else if (ObjCCategoryImplDecl *CatImpl = dyn_cast(ClassDecl)) CurrentClass = CatImpl->getClassInterface(); } ResultTypeCompatibilityKind RTC = CheckRelatedResultTypeCompatibility(*this, ObjCMethod, CurrentClass); CheckObjCMethodOverrides(ObjCMethod, CurrentClass, RTC); bool ARCError = false; if (getLangOpts().ObjCAutoRefCount) ARCError = CheckARCMethodDecl(ObjCMethod); // Infer the related result type when possible. if (!ARCError && RTC == Sema::RTC_Compatible && !ObjCMethod->hasRelatedResultType() && LangOpts.ObjCInferRelatedResultType) { bool InferRelatedResultType = false; switch (ObjCMethod->getMethodFamily()) { case OMF_None: case OMF_copy: case OMF_dealloc: case OMF_finalize: case OMF_mutableCopy: case OMF_release: case OMF_retainCount: case OMF_initialize: case OMF_performSelector: break; case OMF_alloc: case OMF_new: InferRelatedResultType = ObjCMethod->isClassMethod(); break; case OMF_init: case OMF_autorelease: case OMF_retain: case OMF_self: InferRelatedResultType = ObjCMethod->isInstanceMethod(); break; } if (InferRelatedResultType && !ObjCMethod->getReturnType()->isObjCIndependentClassType()) ObjCMethod->SetRelatedResultType(); } ActOnDocumentableDecl(ObjCMethod); return ObjCMethod; } bool Sema::CheckObjCDeclScope(Decl *D) { // Following is also an error. But it is caused by a missing @end // and diagnostic is issued elsewhere. if (isa(CurContext->getRedeclContext())) return false; // If we switched context to translation unit while we are still lexically in // an objc container, it means the parser missed emitting an error. if (isa(getCurLexicalContext()->getRedeclContext())) return false; Diag(D->getLocation(), diag::err_objc_decls_may_only_appear_in_global_scope); D->setInvalidDecl(); return true; } /// Called whenever \@defs(ClassName) is encountered in the source. Inserts the /// instance variables of ClassName into Decls. void Sema::ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart, IdentifierInfo *ClassName, SmallVectorImpl &Decls) { // Check that ClassName is a valid class ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName, DeclStart); if (!Class) { Diag(DeclStart, diag::err_undef_interface) << ClassName; return; } if (LangOpts.ObjCRuntime.isNonFragile()) { Diag(DeclStart, diag::err_atdef_nonfragile_interface); return; } // Collect the instance variables SmallVector Ivars; Context.DeepCollectObjCIvars(Class, true, Ivars); // For each ivar, create a fresh ObjCAtDefsFieldDecl. for (unsigned i = 0; i < Ivars.size(); i++) { const FieldDecl* ID = cast(Ivars[i]); RecordDecl *Record = dyn_cast(TagD); Decl *FD = ObjCAtDefsFieldDecl::Create(Context, Record, /*FIXME: StartL=*/ID->getLocation(), ID->getLocation(), ID->getIdentifier(), ID->getType(), ID->getBitWidth()); Decls.push_back(FD); } // Introduce all of these fields into the appropriate scope. for (SmallVectorImpl::iterator D = Decls.begin(); D != Decls.end(); ++D) { FieldDecl *FD = cast(*D); if (getLangOpts().CPlusPlus) PushOnScopeChains(cast(FD), S); else if (RecordDecl *Record = dyn_cast(TagD)) Record->addDecl(FD); } } /// \brief Build a type-check a new Objective-C exception variable declaration. VarDecl *Sema::BuildObjCExceptionDecl(TypeSourceInfo *TInfo, QualType T, SourceLocation StartLoc, SourceLocation IdLoc, IdentifierInfo *Id, bool Invalid) { // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage // duration shall not be qualified by an address-space qualifier." // Since all parameters have automatic store duration, they can not have // an address space. if (T.getAddressSpace() != 0) { Diag(IdLoc, diag::err_arg_with_address_space); Invalid = true; } // An @catch parameter must be an unqualified object pointer type; // FIXME: Recover from "NSObject foo" by inserting the * in "NSObject *foo"? if (Invalid) { // Don't do any further checking. } else if (T->isDependentType()) { // Okay: we don't know what this type will instantiate to. } else if (!T->isObjCObjectPointerType()) { Invalid = true; Diag(IdLoc ,diag::err_catch_param_not_objc_type); } else if (T->isObjCQualifiedIdType()) { Invalid = true; Diag(IdLoc, diag::err_illegal_qualifiers_on_catch_parm); } VarDecl *New = VarDecl::Create(Context, CurContext, StartLoc, IdLoc, Id, T, TInfo, SC_None); New->setExceptionVariable(true); // In ARC, infer 'retaining' for variables of retainable type. if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(New)) Invalid = true; if (Invalid) New->setInvalidDecl(); return New; } Decl *Sema::ActOnObjCExceptionDecl(Scope *S, Declarator &D) { const DeclSpec &DS = D.getDeclSpec(); // We allow the "register" storage class on exception variables because // GCC did, but we drop it completely. Any other storage class is an error. if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { Diag(DS.getStorageClassSpecLoc(), diag::warn_register_objc_catch_parm) << FixItHint::CreateRemoval(SourceRange(DS.getStorageClassSpecLoc())); } else if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) { Diag(DS.getStorageClassSpecLoc(), diag::err_storage_spec_on_catch_parm) << DeclSpec::getSpecifierName(SCS); } if (DS.isInlineSpecified()) Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function) << getLangOpts().CPlusPlus1z; if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), diag::err_invalid_thread) << DeclSpec::getSpecifierName(TSCS); D.getMutableDeclSpec().ClearStorageClassSpecs(); DiagnoseFunctionSpecifiers(D.getDeclSpec()); // Check that there are no default arguments inside the type of this // exception object (C++ only). if (getLangOpts().CPlusPlus) CheckExtraCXXDefaultArguments(D); TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); QualType ExceptionType = TInfo->getType(); VarDecl *New = BuildObjCExceptionDecl(TInfo, ExceptionType, D.getSourceRange().getBegin(), D.getIdentifierLoc(), D.getIdentifier(), D.isInvalidType()); // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). if (D.getCXXScopeSpec().isSet()) { Diag(D.getIdentifierLoc(), diag::err_qualified_objc_catch_parm) << D.getCXXScopeSpec().getRange(); New->setInvalidDecl(); } // Add the parameter declaration into this scope. S->AddDecl(New); if (D.getIdentifier()) IdResolver.AddDecl(New); ProcessDeclAttributes(S, New, D); if (New->hasAttr()) Diag(New->getLocation(), diag::err_block_on_nonlocal); return New; } /// CollectIvarsToConstructOrDestruct - Collect those ivars which require /// initialization. void Sema::CollectIvarsToConstructOrDestruct(ObjCInterfaceDecl *OI, SmallVectorImpl &Ivars) { for (ObjCIvarDecl *Iv = OI->all_declared_ivar_begin(); Iv; Iv= Iv->getNextIvar()) { QualType QT = Context.getBaseElementType(Iv->getType()); if (QT->isRecordType()) Ivars.push_back(Iv); } } void Sema::DiagnoseUseOfUnimplementedSelectors() { // Load referenced selectors from the external source. if (ExternalSource) { SmallVector, 4> Sels; ExternalSource->ReadReferencedSelectors(Sels); for (unsigned I = 0, N = Sels.size(); I != N; ++I) ReferencedSelectors[Sels[I].first] = Sels[I].second; } // Warning will be issued only when selector table is // generated (which means there is at lease one implementation // in the TU). This is to match gcc's behavior. if (ReferencedSelectors.empty() || !Context.AnyObjCImplementation()) return; for (auto &SelectorAndLocation : ReferencedSelectors) { Selector Sel = SelectorAndLocation.first; SourceLocation Loc = SelectorAndLocation.second; if (!LookupImplementedMethodInGlobalPool(Sel)) Diag(Loc, diag::warn_unimplemented_selector) << Sel; } } ObjCIvarDecl * Sema::GetIvarBackingPropertyAccessor(const ObjCMethodDecl *Method, const ObjCPropertyDecl *&PDecl) const { if (Method->isClassMethod()) return nullptr; const ObjCInterfaceDecl *IDecl = Method->getClassInterface(); if (!IDecl) return nullptr; Method = IDecl->lookupMethod(Method->getSelector(), /*isInstance=*/true, /*shallowCategoryLookup=*/false, /*followSuper=*/false); if (!Method || !Method->isPropertyAccessor()) return nullptr; if ((PDecl = Method->findPropertyDecl())) if (ObjCIvarDecl *IV = PDecl->getPropertyIvarDecl()) { // property backing ivar must belong to property's class // or be a private ivar in class's implementation. // FIXME. fix the const-ness issue. IV = const_cast(IDecl)->lookupInstanceVariable( IV->getIdentifier()); return IV; } return nullptr; } namespace { /// Used by Sema::DiagnoseUnusedBackingIvarInAccessor to check if a property /// accessor references the backing ivar. class UnusedBackingIvarChecker : public RecursiveASTVisitor { public: Sema &S; const ObjCMethodDecl *Method; const ObjCIvarDecl *IvarD; bool AccessedIvar; bool InvokedSelfMethod; UnusedBackingIvarChecker(Sema &S, const ObjCMethodDecl *Method, const ObjCIvarDecl *IvarD) : S(S), Method(Method), IvarD(IvarD), AccessedIvar(false), InvokedSelfMethod(false) { assert(IvarD); } bool VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { if (E->getDecl() == IvarD) { AccessedIvar = true; return false; } return true; } bool VisitObjCMessageExpr(ObjCMessageExpr *E) { if (E->getReceiverKind() == ObjCMessageExpr::Instance && S.isSelfExpr(E->getInstanceReceiver(), Method)) { InvokedSelfMethod = true; } return true; } }; } // end anonymous namespace void Sema::DiagnoseUnusedBackingIvarInAccessor(Scope *S, const ObjCImplementationDecl *ImplD) { if (S->hasUnrecoverableErrorOccurred()) return; for (const auto *CurMethod : ImplD->instance_methods()) { unsigned DIAG = diag::warn_unused_property_backing_ivar; SourceLocation Loc = CurMethod->getLocation(); if (Diags.isIgnored(DIAG, Loc)) continue; const ObjCPropertyDecl *PDecl; const ObjCIvarDecl *IV = GetIvarBackingPropertyAccessor(CurMethod, PDecl); if (!IV) continue; UnusedBackingIvarChecker Checker(*this, CurMethod, IV); Checker.TraverseStmt(CurMethod->getBody()); if (Checker.AccessedIvar) continue; // Do not issue this warning if backing ivar is used somewhere and accessor // implementation makes a self call. This is to prevent false positive in // cases where the ivar is accessed by another method that the accessor // delegates to. if (!IV->isReferenced() || !Checker.InvokedSelfMethod) { Diag(Loc, DIAG) << IV; Diag(PDecl->getLocation(), diag::note_property_declare); } } }